18547961 has 2 divisors, whose sum is σ = 18547962. Its totient is φ = 18547960.

The previous prime is 18547957. The next prime is 18547973. The reversal of 18547961 is 16974581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11424400 + 7123561 = 3380^2 + 2669^2 .

It is a cyclic number.

It is not a de Polignac number, because 18547961 - 2² = 18547957 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (18547981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9273980 + 9273981.

It is an arithmetic number, because the mean of its divisors is an integer number (9273981).

Almost surely, 2^18547961 is an apocalyptic number.

It is an amenable number.

18547961 is a deficient number, since it is larger than the sum of its proper divisors (1).

18547961 is an equidigital number, since it uses as much as digits as its factorization.

18547961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 60480, while the sum is 41.

The square root of 18547961 is about 4306.7343776927. The cubic root of 18547961 is about 264.7069788316.

The spelling of 18547961 in words is "eighteen million, five hundred forty-seven thousand, nine hundred sixty-one".