21455131152 has 160 divisors (see below), whose sum is σ = 68284518400. Its totient is φ = 5652840960.

The previous prime is 21455131109. The next prime is 21455131153. The reversal of 21455131152 is 25113155412.

It is not an unprimeable number, because it can be changed into a prime (21455131153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6109077 + ... + 6112587.

It is an arithmetic number, because the mean of its divisors is an integer number (426778240).

Almost surely, 2^21455131152 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 21455131152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34142259200).

21455131152 is an abundant number, since it is smaller than the sum of its proper divisors (46829387248).

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

21455131152 is a wasteful number, since it uses less digits than its factorization.

21455131152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4941 (or 4935 counting only the distinct ones).

The product of its digits is 6000, while the sum is 30.

Adding to 21455131152 its reverse (25113155412), we get a palindrome (46568286564).

The spelling of 21455131152 in words is "twenty-one billion, four hundred fifty-five million, one hundred thirty-one thousand, one hundred fifty-two".