87463721 has 2 divisors, whose sum is σ = 87463722. Its totient is φ = 87463720.

The previous prime is 87463699. The next prime is 87463729. The reversal of 87463721 is 12736478.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54228496 + 33235225 = 7364^2 + 5765^2 .

It is a cyclic number.

It is not a de Polignac number, because 87463721 - 2²⁶ = 20354857 is a prime.

It is equal to p_5078477 and since 87463721 and 5078477 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (87463729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43731860 + 43731861.

It is an arithmetic number, because the mean of its divisors is an integer number (43731861).

Almost surely, 2^87463721 is an apocalyptic number.

It is an amenable number.

87463721 is a deficient number, since it is larger than the sum of its proper divisors (1).

87463721 is an equidigital number, since it uses as much as digits as its factorization.

87463721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 38.

The square root of 87463721 is about 9352.2040717683. The cubic root of 87463721 is about 443.8906356861.

The spelling of 87463721 in words is "eighty-seven million, four hundred sixty-three thousand, seven hundred twenty-one".