90610921820 has 24 divisors (see below), whose sum is σ = 194708122224. Its totient is φ = 35401476096.

The previous prime is 90610921811. The next prime is 90610921823. The reversal of 90610921820 is 2812901609.

It is a super-2 number, since 2×90610921820² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (90610921823) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52679909 + ... + 52681628.

It is an arithmetic number, because the mean of its divisors is an integer number (8112838426).

Almost surely, 2^90610921820 is an apocalyptic number.

It is an amenable number.

90610921820 is an abundant number, since it is smaller than the sum of its proper divisors (104097200404).

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

90610921820 is a wasteful number, since it uses less digits than its factorization.

90610921820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105361589 (or 105361587 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 38.

The spelling of 90610921820 in words is "ninety billion, six hundred ten million, nine hundred twenty-one thousand, eight hundred twenty".