90212779 has 6 divisors (see below), whose sum is σ = 95004420. Its totient is φ = 85425516.

The previous prime is 90212777. The next prime is 90212789. The reversal of 90212779 is 97721209.

It is not a de Polignac number, because 90212779 - 2¹ = 90212777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90212777) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 40312 + ... + 42490.

It is an arithmetic number, because the mean of its divisors is an integer number (15834070).

Almost surely, 2^90212779 is an apocalyptic number.

90212779 is a deficient number, since it is larger than the sum of its proper divisors (4791641).

90212779 is an frugal number, since it uses more digits than its factorization.

90212779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4377 (or 2198 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 90212779 is about 9498.0407979751. The cubic root of 90212779 is about 448.4933629307.

The spelling of 90212779 in words is "ninety million, two hundred twelve thousand, seven hundred seventy-nine".