20120111101957 has 2 divisors, whose sum is σ = 20120111101958. Its totient is φ = 20120111101956.

The previous prime is 20120111101939. The next prime is 20120111102029. The reversal of 20120111101957 is 75910111102102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17606827210401 + 2513283891556 = 4196049^2 + 1585334^2 .

It is a cyclic number.

It is not a de Polignac number, because 20120111101957 - 2²³ = 20120102713349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20120811101957) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10060055550978 + 10060055550979.

It is an arithmetic number, because the mean of its divisors is an integer number (10060055550979).

Almost surely, 2^{20120111101957} is an apocalyptic number.

It is an amenable number.

20120111101957 is a deficient number, since it is larger than the sum of its proper divisors (1).

20120111101957 is an equidigital number, since it uses as much as digits as its factorization.

20120111101957 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1260, while the sum is 31.

The spelling of 20120111101957 in words is "twenty trillion, one hundred twenty billion, one hundred eleven million, one hundred one thousand, nine hundred fifty-seven".