90999012 has 72 divisors (see below), whose sum is σ = 236667648. Its totient is φ = 27051840.

The previous prime is 90998989. The next prime is 90999023. The reversal of 90999012 is 21099909.

It is a happy number.

It is a super-2 number, since 2×90999012² = 16561640369952288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 149613 + ... + 150219.

Almost surely, 2^90999012 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90999012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (118333824).

90999012 is an abundant number, since it is smaller than the sum of its proper divisors (145668636).

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

90999012 is a wasteful number, since it uses less digits than its factorization.

90999012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 689 (or 656 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 39.

The square root of 90999012 is about 9539.3402287580. The cubic root of 90999012 is about 449.7925166952.

The spelling of 90999012 in words is "ninety million, nine hundred ninety-nine thousand, twelve".