11921957 has 2 divisors, whose sum is σ = 11921958. Its totient is φ = 11921956.

The previous prime is 11921933. The next prime is 11921977. The reversal of 11921957 is 75912911.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5997601 + 5924356 = 2449^2 + 2434^2 .

It is a cyclic number.

It is not a de Polignac number, because 11921957 - 2²⁰ = 10873381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11921977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5960978 + 5960979.

It is an arithmetic number, because the mean of its divisors is an integer number (5960979).

Almost surely, 2^11921957 is an apocalyptic number.

It is an amenable number.

11921957 is a deficient number, since it is larger than the sum of its proper divisors (1).

11921957 is an equidigital number, since it uses as much as digits as its factorization.

11921957 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5670, while the sum is 35.

The square root of 11921957 is about 3452.8187036101. The cubic root of 11921957 is about 228.4454523635.

The spelling of 11921957 in words is "eleven million, nine hundred twenty-one thousand, nine hundred fifty-seven".