38997712891 has 2 divisors, whose sum is σ = 38997712892. Its totient is φ = 38997712890.

The previous prime is 38997712883. The next prime is 38997712927. The reversal of 38997712891 is 19821779983.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 38997712891 - 2³ = 38997712883 is a prime.

It is a super-2 number, since 2×38997712891² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (38997712841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19498856445 + 19498856446.

It is an arithmetic number, because the mean of its divisors is an integer number (19498856446).

Almost surely, 2^38997712891 is an apocalyptic number.

38997712891 is a deficient number, since it is larger than the sum of its proper divisors (1).

38997712891 is an equidigital number, since it uses as much as digits as its factorization.

38997712891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13716864, while the sum is 64.

The spelling of 38997712891 in words is "thirty-eight billion, nine hundred ninety-seven million, seven hundred twelve thousand, eight hundred ninety-one".