90978805 has 8 divisors (see below), whose sum is σ = 110670552. Its totient is φ = 71785728.

The previous prime is 90978787. The next prime is 90978827. The reversal of 90978805 is 50887909.

It can be written as a sum of positive squares in 4 ways, for example, as 39225169 + 51753636 = 6263^2 + 7194^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 90978805 - 2⁵ = 90978773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 124264 + ... + 124993.

It is an arithmetic number, because the mean of its divisors is an integer number (13833819).

Almost surely, 2^90978805 is an apocalyptic number.

It is an amenable number.

90978805 is a deficient number, since it is larger than the sum of its proper divisors (19691747).

90978805 is a wasteful number, since it uses less digits than its factorization.

90978805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249335.

The product of its (nonzero) digits is 181440, while the sum is 46.

The square root of 90978805 is about 9538.2810296195. The cubic root of 90978805 is about 449.7592209849.

The spelling of 90978805 in words is "ninety million, nine hundred seventy-eight thousand, eight hundred five".