18687401 has 2 divisors, whose sum is σ = 18687402. Its totient is φ = 18687400.

The previous prime is 18687391. The next prime is 18687407. The reversal of 18687401 is 10478681.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18284176 + 403225 = 4276^2 + 635^2 .

It is a cyclic number.

It is not a de Polignac number, because 18687401 - 2¹⁰ = 18686377 is a prime.

It is a super-2 number, since 2×18687401² = 698437912269602, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (18687407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9343700 + 9343701.

It is an arithmetic number, because the mean of its divisors is an integer number (9343701).

Almost surely, 2^18687401 is an apocalyptic number.

It is an amenable number.

18687401 is a deficient number, since it is larger than the sum of its proper divisors (1).

18687401 is an equidigital number, since it uses as much as digits as its factorization.

18687401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10752, while the sum is 35.

The square root of 18687401 is about 4322.8926657968. The cubic root of 18687401 is about 265.3686621575.

The spelling of 18687401 in words is "eighteen million, six hundred eighty-seven thousand, four hundred one".