20258508990 has 128 divisors (see below), whose sum is σ = 51727822848. Its totient is φ = 5068707840.

The previous prime is 20258508929. The next prime is 20258509009. The reversal of 20258508990 is 9980585202.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11595297 + ... + 11597043.

It is an arithmetic number, because the mean of its divisors is an integer number (404123616).

Almost surely, 2^20258508990 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20258508990, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25863911424).

20258508990 is an abundant number, since it is smaller than the sum of its proper divisors (31469313858).

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

20258508990 is a wasteful number, since it uses less digits than its factorization.

20258508990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2162.

The product of its (nonzero) digits is 518400, while the sum is 48.

The spelling of 20258508990 in words is "twenty billion, two hundred fifty-eight million, five hundred eight thousand, nine hundred ninety".