21131041456 has 60 divisors (see below), whose sum is σ = 47750729472. Its totient is φ = 9032386944.

The previous prime is 21131041447. The next prime is 21131041489. The reversal of 21131041456 is 65414013112.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 265086 + ... + 335458.

Almost surely, 2^21131041456 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 21131041456, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23875364736).

21131041456 is an abundant number, since it is smaller than the sum of its proper divisors (26619688016).

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

21131041456 is a wasteful number, since it uses less digits than its factorization.

21131041456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70778 (or 70765 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 28.

Adding to 21131041456 its reverse (65414013112), we get a palindrome (86545054568).

The spelling of 21131041456 in words is "twenty-one billion, one hundred thirty-one million, forty-one thousand, four hundred fifty-six".