20658990 has 32 divisors (see below), whose sum is σ = 54089856. Its totient is φ = 5008160.

The previous prime is 20658983. The next prime is 20658997. The reversal of 20658990 is 9985602.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20658983) and next prime (20658997).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20658997) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30972 + ... + 31631.

It is an arithmetic number, because the mean of its divisors is an integer number (1690308).

Almost surely, 2^20658990 is an apocalyptic number.

20658990 is an abundant number, since it is smaller than the sum of its proper divisors (33430866).

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

20658990 is a wasteful number, since it uses less digits than its factorization.

20658990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62624.

The product of its (nonzero) digits is 38880, while the sum is 39.

The square root of 20658990 is about 4545.2161664766. The cubic root of 20658990 is about 274.3908942939.

The spelling of 20658990 in words is "twenty million, six hundred fifty-eight thousand, nine hundred ninety".