18956461 has 2 divisors, whose sum is σ = 18956462. Its totient is φ = 18956460.

The previous prime is 18956449. The next prime is 18956467. The reversal of 18956461 is 16465981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11222500 + 7733961 = 3350^2 + 2781^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18956461 is a prime.

It is a nialpdrome in base 12.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18956467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9478230 + 9478231.

It is an arithmetic number, because the mean of its divisors is an integer number (9478231).

Almost surely, 2^18956461 is an apocalyptic number.

It is an amenable number.

18956461 is a deficient number, since it is larger than the sum of its proper divisors (1).

18956461 is an equidigital number, since it uses as much as digits as its factorization.

18956461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 51840, while the sum is 40.

The square root of 18956461 is about 4353.9018133164. The cubic root of 18956461 is about 266.6361852312.

The spelling of 18956461 in words is "eighteen million, nine hundred fifty-six thousand, four hundred sixty-one".