87557861 has 2 divisors, whose sum is σ = 87557862. Its totient is φ = 87557860.

The previous prime is 87557819. The next prime is 87557867. The reversal of 87557861 is 16875578.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68145025 + 19412836 = 8255^2 + 4406^2 .

It is a cyclic number.

It is not a de Polignac number, because 87557861 - 2⁶ = 87557797 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87557867) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43778930 + 43778931.

It is an arithmetic number, because the mean of its divisors is an integer number (43778931).

Almost surely, 2^87557861 is an apocalyptic number.

It is an amenable number.

87557861 is a deficient number, since it is larger than the sum of its proper divisors (1).

87557861 is an equidigital number, since it uses as much as digits as its factorization.

87557861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 470400, while the sum is 47.

The square root of 87557861 is about 9357.2357563545. The cubic root of 87557861 is about 444.0498364777.

The spelling of 87557861 in words is "eighty-seven million, five hundred fifty-seven thousand, eight hundred sixty-one".