20199990 has 32 divisors (see below), whose sum is σ = 48625920. Its totient is φ = 5370464.

The previous prime is 20199973. The next prime is 20200013. The reversal of 20199990 is 9999102.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11767 + ... + 13373.

It is an arithmetic number, because the mean of its divisors is an integer number (1519560).

Almost surely, 2^20199990 is an apocalyptic number.

20199990 is an abundant number, since it is smaller than the sum of its proper divisors (28425930).

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

20199990 is a wasteful number, since it uses less digits than its factorization.

20199990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2036.

The product of its (nonzero) digits is 13122, while the sum is 39.

The square root of 20199990 is about 4494.4398983633. The cubic root of 20199990 is about 272.3435232157.

The spelling of 20199990 in words is "twenty million, one hundred ninety-nine thousand, nine hundred ninety".