18901957 has 2 divisors, whose sum is σ = 18901958. Its totient is φ = 18901956.

The previous prime is 18901951. The next prime is 18902041. The reversal of 18901957 is 75910981.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12173121 + 6728836 = 3489^2 + 2594^2 .

It is a cyclic number.

It is not a de Polignac number, because 18901957 - 2⁷ = 18901829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18901951) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9450978 + 9450979.

It is an arithmetic number, because the mean of its divisors is an integer number (9450979).

Almost surely, 2^18901957 is an apocalyptic number.

It is an amenable number.

18901957 is a deficient number, since it is larger than the sum of its proper divisors (1).

18901957 is an equidigital number, since it uses as much as digits as its factorization.

18901957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 40.

The square root of 18901957 is about 4347.6380944140. The cubic root of 18901957 is about 266.3803940051.

The spelling of 18901957 in words is "eighteen million, nine hundred one thousand, nine hundred fifty-seven".