90219820 has 12 divisors (see below), whose sum is σ = 189461664. Its totient is φ = 36087920.

The previous prime is 90219781. The next prime is 90219851. The reversal of 90219820 is 2891209.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2255476 + ... + 2255515.

It is an arithmetic number, because the mean of its divisors is an integer number (15788472).

Almost surely, 2^90219820 is an apocalyptic number.

It is an amenable number.

90219820 is an abundant number, since it is smaller than the sum of its proper divisors (99241844).

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

90219820 is a wasteful number, since it uses less digits than its factorization.

90219820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4511000 (or 4510998 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 90219820 is about 9498.4114461314. The cubic root of 90219820 is about 448.5050307515.

The spelling of 90219820 in words is "ninety million, two hundred nineteen thousand, eight hundred twenty".