90812778 has 24 divisors (see below), whose sum is σ = 211279392. Its totient is φ = 25946424.

The previous prime is 90812767. The next prime is 90812783. The reversal of 90812778 is 87721809.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 154150 + ... + 154737.

It is an arithmetic number, because the mean of its divisors is an integer number (8803308).

Almost surely, 2^90812778 is an apocalyptic number.

90812778 is a gapful number since it is divisible by the number (98) formed by its first and last digit.

90812778 is an abundant number, since it is smaller than the sum of its proper divisors (120466614).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

90812778 is a wasteful number, since it uses less digits than its factorization.

90812778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308906 (or 308899 counting only the distinct ones).

The product of its (nonzero) digits is 56448, while the sum is 42.

The square root of 90812778 is about 9529.5738624558. The cubic root of 90812778 is about 449.4854662230.

The spelling of 90812778 in words is "ninety million, eight hundred twelve thousand, seven hundred seventy-eight".