21265494760 has 32 divisors (see below), whose sum is σ = 47854389960. Its totient is φ = 8504948736.

The previous prime is 21265494713. The next prime is 21265494787. The reversal of 21265494760 is 6749456212.

It can be written as a sum of positive squares in 4 ways, for example, as 20295421444 + 970073316 = 142462^2 + 31146^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21265494760.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 266212 + ... + 336748.

Almost surely, 2^21265494760 is an apocalyptic number.

21265494760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21265494760 is an abundant number, since it is smaller than the sum of its proper divisors (26588895200).

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

21265494760 is a wasteful number, since it uses less digits than its factorization.

21265494760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78085 (or 78081 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 46.

The spelling of 21265494760 in words is "twenty-one billion, two hundred sixty-five million, four hundred ninety-four thousand, seven hundred sixty".