21000526731 has 12 divisors (see below), whose sum is σ = 30353061960. Its totient is φ = 13991596800.

The previous prime is 21000526693. The next prime is 21000526741. The reversal of 21000526731 is 13762500012.

It is a happy number.

21000526731 is a `hidden beast` number, since 2 + 100 + 0 + 526 + 7 + 31 = 666.

It is not a de Polignac number, because 21000526731 - 2¹⁵ = 21000493963 is a prime.

It is a super-2 number, since 2×21000526731² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21000526695 and 21000526704.

It is not an unprimeable number, because it can be changed into a prime (21000526741) 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, 714321 + ... + 743138.

It is an arithmetic number, because the mean of its divisors is an integer number (2529421830).

Almost surely, 2^21000526731 is an apocalyptic number.

21000526731 is a deficient number, since it is larger than the sum of its proper divisors (9352535229).

21000526731 is a wasteful number, since it uses less digits than its factorization.

21000526731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1459066 (or 1459063 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The spelling of 21000526731 in words is "twenty-one billion, five hundred twenty-six thousand, seven hundred thirty-one".