87291985 has 32 divisors (see below), whose sum is σ = 121605120. Its totient is φ = 59486400.

The previous prime is 87291979. The next prime is 87292031. The reversal of 87291985 is 58919278.

87291985 is nontrivially palindromic in base 6.

It is not a de Polignac number, because 87291985 - 2²¹ = 85194833 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 107230 + ... + 108040.

It is an arithmetic number, because the mean of its divisors is an integer number (3800160).

It is a vampire number, since it can be written as 8921 ⋅ 9785 (with its own digits).

Almost surely, 2^87291985 is an apocalyptic number.

It is an amenable number.

87291985 is a deficient number, since it is larger than the sum of its proper divisors (34313135).

87291985 is a wasteful number, since it uses less digits than its factorization.

87291985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 949.

The product of its digits is 362880, while the sum is 49.

The square root of 87291985 is about 9343.0179813591. The cubic root of 87291985 is about 443.5999172413.

The spelling of 87291985 in words is "eighty-seven million, two hundred ninety-one thousand, nine hundred eighty-five".