20397581051 has 2 divisors, whose sum is σ = 20397581052. Its totient is φ = 20397581050.

The previous prime is 20397581047. The next prime is 20397581063. The reversal of 20397581051 is 15018579302.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20397581051 - 2² = 20397581047 is a prime.

It is a super-2 number, since 2×20397581051² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20397581251) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10198790525 + 10198790526.

It is an arithmetic number, because the mean of its divisors is an integer number (10198790526).

Almost surely, 2^20397581051 is an apocalyptic number.

20397581051 is a deficient number, since it is larger than the sum of its proper divisors (1).

20397581051 is an equidigital number, since it uses as much as digits as its factorization.

20397581051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 75600, while the sum is 41.

The spelling of 20397581051 in words is "twenty billion, three hundred ninety-seven million, five hundred eighty-one thousand, fifty-one".