87678989 has 4 divisors (see below), whose sum is σ = 87781920. Its totient is φ = 87576060.

The previous prime is 87678971. The next prime is 87678991. The reversal of 87678989 is 98987678.

87678989 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 87678989 - 2²⁰ = 86630413 is a prime.

It is a super-2 number, since 2×87678989² = 15375210224124242, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87678949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50177 + ... + 51894.

It is an arithmetic number, because the mean of its divisors is an integer number (21945480).

Almost surely, 2^87678989 is an apocalyptic number.

It is an amenable number.

87678989 is a deficient number, since it is larger than the sum of its proper divisors (102931).

87678989 is a wasteful number, since it uses less digits than its factorization.

87678989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102930.

The product of its digits is 12192768, while the sum is 62.

The square root of 87678989 is about 9363.7059436956. The cubic root of 87678989 is about 444.2545090756.

The spelling of 87678989 in words is "eighty-seven million, six hundred seventy-eight thousand, nine hundred eighty-nine".