18761957 has 2 divisors, whose sum is σ = 18761958. Its totient is φ = 18761956.

The previous prime is 18761933. The next prime is 18761959. The reversal of 18761957 is 75916781.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14737921 + 4024036 = 3839^2 + 2006^2 .

It is a cyclic number.

It is not a de Polignac number, because 18761957 - 2¹⁶ = 18696421 is a prime.

It is a super-2 number, since 2×18761957² = 704022060939698, which contains 22 as substring.

Together with 18761959, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18761959) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9380978 + 9380979.

It is an arithmetic number, because the mean of its divisors is an integer number (9380979).

Almost surely, 2^18761957 is an apocalyptic number.

It is an amenable number.

18761957 is a deficient number, since it is larger than the sum of its proper divisors (1).

18761957 is an equidigital number, since it uses as much as digits as its factorization.

18761957 is an evil number, because the sum of its binary digits is even.

The product of its digits is 105840, while the sum is 44.

The square root of 18761957 is about 4331.5074743096. The cubic root of 18761957 is about 265.7211023335.

The spelling of 18761957 in words is "eighteen million, seven hundred sixty-one thousand, nine hundred fifty-seven".