90851191920 has 640 divisors, whose sum is σ = 352327449600. Its totient is φ = 21382299648.

The previous prime is 90851191877. The next prime is 90851191957. The reversal of 90851191920 is 2919115809.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 74651152 + ... + 74652368.

It is an arithmetic number, because the mean of its divisors is an integer number (550511640).

Almost surely, 2^90851191920 is an apocalyptic number.

90851191920 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 90851191920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (176163724800).

90851191920 is an abundant number, since it is smaller than the sum of its proper divisors (261476257680).

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

90851191920 is a wasteful number, since it uses less digits than its factorization.

90851191920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1382 (or 1370 counting only the distinct ones).

The product of its (nonzero) digits is 58320, while the sum is 45.

The spelling of 90851191920 in words is "ninety billion, eight hundred fifty-one million, one hundred ninety-one thousand, nine hundred twenty".