21535267023 has 12 divisors (see below), whose sum is σ = 32109932608. Its totient is φ = 13893720480.

The previous prime is 21535267007. The next prime is 21535267031. The reversal of 21535267023 is 32076253512.

21535267023 is a `hidden beast` number, since 215 + 352 + 6 + 70 + 23 = 666.

It is not a de Polignac number, because 21535267023 - 2⁴ = 21535267007 is a prime.

It is a super-2 number, since 2×21535267023² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21535267003) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38593390 + ... + 38593947.

Almost surely, 2^21535267023 is an apocalyptic number.

21535267023 is a deficient number, since it is larger than the sum of its proper divisors (10574665585).

21535267023 is a wasteful number, since it uses less digits than its factorization.

21535267023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77187374 (or 77187371 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 36.

The spelling of 21535267023 in words is "twenty-one billion, five hundred thirty-five million, two hundred sixty-seven thousand, twenty-three".