21012732965 has 24 divisors (see below), whose sum is σ = 29346944760. Its totient is φ = 14401419648.

The previous prime is 21012732941. The next prime is 21012732967. The reversal of 21012732965 is 56923721012.

It can be written as a sum of positive squares in 4 ways, for example, as 287675521 + 20725057444 = 16961^2 + 143962^2 .

It is not a de Polignac number, because 21012732965 - 2¹⁴ = 21012716581 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012732967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 486179 + ... + 527631.

It is an arithmetic number, because the mean of its divisors is an integer number (1222789365).

Almost surely, 2^21012732965 is an apocalyptic number.

It is an amenable number.

21012732965 is a deficient number, since it is larger than the sum of its proper divisors (8334211795).

21012732965 is a wasteful number, since it uses less digits than its factorization.

21012732965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43541 (or 43534 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 38.

The spelling of 21012732965 in words is "twenty-one billion, twelve million, seven hundred thirty-two thousand, nine hundred sixty-five".