87164981 has 8 divisors (see below), whose sum is σ = 90381720. Its totient is φ = 83962368.

The previous prime is 87164953. The next prime is 87165031. The reversal of 87164981 is 18946178.

It can be written as a sum of positive squares in 4 ways, for example, as 57896881 + 29268100 = 7609^2 + 5410^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-87164981 is a prime.

It is a super-2 number, since 2×87164981² = 15195467825460722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87164921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9965 + ... + 16541.

It is an arithmetic number, because the mean of its divisors is an integer number (11297715).

Almost surely, 2^87164981 is an apocalyptic number.

It is an amenable number.

87164981 is a deficient number, since it is larger than the sum of its proper divisors (3216739).

87164981 is a wasteful number, since it uses less digits than its factorization.

87164981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7063.

The product of its digits is 96768, while the sum is 44.

The square root of 87164981 is about 9336.2187742148. The cubic root of 87164981 is about 443.3846767503.

The spelling of 87164981 in words is "eighty-seven million, one hundred sixty-four thousand, nine hundred eighty-one".