21347989372938 has 16 divisors (see below), whose sum is σ = 42706807091136. Its totient is φ = 7114191733440.

The previous prime is 21347989372841. The next prime is 21347989372939. The reversal of 21347989372938 is 83927398974312.

It is a self number, because there is not a number n which added to its sum of digits gives 21347989372938.

It is not an unprimeable number, because it can be changed into a prime (21347989372939) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 451155423 + ... + 451202738.

It is an arithmetic number, because the mean of its divisors is an integer number (2669175443196).

Almost surely, 2^{21347989372938} is an apocalyptic number.

21347989372938 is an abundant number, since it is smaller than the sum of its proper divisors (21358817718198).

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

21347989372938 is a wasteful number, since it uses less digits than its factorization.

21347989372938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 902362109.

The product of its digits is 987614208, while the sum is 75.

The spelling of 21347989372938 in words is "twenty-one trillion, three hundred forty-seven billion, nine hundred eighty-nine million, three hundred seventy-two thousand, nine hundred thirty-eight".