2157431436 has 60 divisors (see below), whose sum is σ = 5668462800. Its totient is φ = 715508640.

The previous prime is 2157431431. The next prime is 2157431449. The reversal of 2157431436 is 6341347512.

2157431436 is a `hidden beast` number, since 21 + 574 + 31 + 4 + 36 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 2157431436.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2157431431) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 47746 + ... + 81206.

It is an arithmetic number, because the mean of its divisors is an integer number (94474380).

Almost surely, 2^2157431436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2157431436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2834231400).

2157431436 is an abundant number, since it is smaller than the sum of its proper divisors (3511031364).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2157431436 is a wasteful number, since it uses less digits than its factorization.

2157431436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33676 (or 33665 counting only the distinct ones).

The product of its digits is 60480, while the sum is 36.

The square root of 2157431436 is about 46448.1585856748. The cubic root of 2157431436 is about 1292.1482215800.

Adding to 2157431436 its reverse (6341347512), we get a palindrome (8498778948).

The spelling of 2157431436 in words is "two billion, one hundred fifty-seven million, four hundred thirty-one thousand, four hundred thirty-six".