87478613 has 2 divisors, whose sum is σ = 87478614. Its totient is φ = 87478612.

The previous prime is 87478561. The next prime is 87478627. The reversal of 87478613 is 31687478.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87478609 + 4 = 9353^2 + 2^2 .

It is a cyclic number.

It is not a de Polignac number, because 87478613 - 2⁸ = 87478357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87478513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43739306 + 43739307.

It is an arithmetic number, because the mean of its divisors is an integer number (43739307).

Almost surely, 2^87478613 is an apocalyptic number.

It is an amenable number.

87478613 is a deficient number, since it is larger than the sum of its proper divisors (1).

87478613 is an equidigital number, since it uses as much as digits as its factorization.

87478613 is an evil number, because the sum of its binary digits is even.

The product of its digits is 225792, while the sum is 44.

The square root of 87478613 is about 9353.0002138351. Note that the first 3 decimals coincide. The cubic root of 87478613 is about 443.9158272518.

The spelling of 87478613 in words is "eighty-seven million, four hundred seventy-eight thousand, six hundred thirteen".