21431440002 has 32 divisors (see below), whose sum is σ = 49789206144. Its totient is φ = 6022886400.

The previous prime is 21431439989. The next prime is 21431440039. The reversal of 21431440002 is 20004413412.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4179999 + ... + 4185122.

It is an arithmetic number, because the mean of its divisors is an integer number (1555912692).

Almost surely, 2^21431440002 is an apocalyptic number.

21431440002 is an abundant number, since it is smaller than the sum of its proper divisors (28357766142).

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

21431440002 is a wasteful number, since it uses less digits than its factorization.

21431440002 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8365194.

The product of its (nonzero) digits is 768, while the sum is 21.

Adding to 21431440002 its reverse (20004413412), we get a palindrome (41435853414).

The spelling of 21431440002 in words is "twenty-one billion, four hundred thirty-one million, four hundred forty thousand, two".