21040023331 has 16 divisors (see below), whose sum is σ = 22479408000. Its totient is φ = 19635239808.

The previous prime is 21040023307. The next prime is 21040023343. The reversal of 21040023331 is 13332004012.

It is a cyclic number.

It is not a de Polignac number, because 21040023331 - 2⁷ = 21040023203 is a prime.

It is a super-2 number, since 2×21040023331² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21040023299 and 21040023308.

It is not an unprimeable number, because it can be changed into a prime (21040024331) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 527995 + ... + 566443.

It is an arithmetic number, because the mean of its divisors is an integer number (1404963000).

Almost surely, 2^21040023331 is an apocalyptic number.

21040023331 is a deficient number, since it is larger than the sum of its proper divisors (1439384669).

21040023331 is a wasteful number, since it uses less digits than its factorization.

21040023331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38898.

The product of its (nonzero) digits is 432, while the sum is 19.

Adding to 21040023331 its reverse (13332004012), we get a palindrome (34372027343).

The spelling of 21040023331 in words is "twenty-one billion, forty million, twenty-three thousand, three hundred thirty-one".