21357962388 has 60 divisors (see below), whose sum is σ = 63810215392. Its totient is φ = 6102274320.

The previous prime is 21357962387. The next prime is 21357962407. The reversal of 21357962388 is 88326975312.

21357962388 is a `hidden beast` number, since 2 + 1 + 3 + 5 + 7 + 9 + 623 + 8 + 8 = 666.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21357962383) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 4706278 + ... + 4710813.

Almost surely, 2^21357962388 is an apocalyptic number.

21357962388 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21357962388 is an abundant number, since it is smaller than the sum of its proper divisors (42452253004).

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

21357962388 is a wasteful number, since it uses less digits than its factorization.

21357962388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9417114 (or 9417103 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 21357962388 in words is "twenty-one billion, three hundred fifty-seven million, nine hundred sixty-two thousand, three hundred eighty-eight".