21263440032 has 48 divisors (see below), whose sum is σ = 62018369280. Its totient is φ = 7087813056.

The previous prime is 21263440031. The next prime is 21263440043. The reversal of 21263440032 is 23004436212.

21263440032 is a `hidden beast` number, since 21 + 2 + 634 + 4 + 0 + 0 + 3 + 2 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×21263440032² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21263439978 and 21263440005.

It is not an unprimeable number, because it can be changed into a prime (21263440031) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12304368 + ... + 12306095.

It is an arithmetic number, because the mean of its divisors is an integer number (1292049360).

Almost surely, 2^21263440032 is an apocalyptic number.

It is an amenable number.

21263440032 is an abundant number, since it is smaller than the sum of its proper divisors (40754929248).

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

21263440032 is a wasteful number, since it uses less digits than its factorization.

21263440032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24610482 (or 24610468 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 27.

Adding to 21263440032 its reverse (23004436212), we get a palindrome (44267876244).

The spelling of 21263440032 in words is "twenty-one billion, two hundred sixty-three million, four hundred forty thousand, thirty-two".