20909190 has 32 divisors (see below), whose sum is σ = 51803136. Its totient is φ = 5395680.

The previous prime is 20909183. The next prime is 20909209. The reversal of 20909190 is 9190902.

It is a super-2 number, since 2×20909190² = 874388452912200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

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, 10312 + ... + 12171.

It is an arithmetic number, because the mean of its divisors is an integer number (1618848).

Almost surely, 2^20909190 is an apocalyptic number.

20909190 is an abundant number, since it is smaller than the sum of its proper divisors (30893946).

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

20909190 is a wasteful number, since it uses less digits than its factorization.

20909190 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22524.

The product of its (nonzero) digits is 1458, while the sum is 30.

The square root of 20909190 is about 4572.6567769733. The cubic root of 20909190 is about 275.4941638174.

The spelling of 20909190 in words is "twenty million, nine hundred nine thousand, one hundred ninety".