21152928340 has 12 divisors (see below), whose sum is σ = 44421149556. Its totient is φ = 8461171328.

The previous prime is 21152928319. The next prime is 21152928343. The reversal of 21152928340 is 4382925112.

It can be written as a sum of positive squares in 2 ways, for example, as 16830391824 + 4322536516 = 129732^2 + 65746^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21152928340.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21152928343) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 528823189 + ... + 528823228.

It is an arithmetic number, because the mean of its divisors is an integer number (3701762463).

Almost surely, 2^21152928340 is an apocalyptic number.

21152928340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21152928340 is an abundant number, since it is smaller than the sum of its proper divisors (23268221216).

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

21152928340 is a wasteful number, since it uses less digits than its factorization.

21152928340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1057646426 (or 1057646424 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 37.

The spelling of 21152928340 in words is "twenty-one billion, one hundred fifty-two million, nine hundred twenty-eight thousand, three hundred forty".