20974290 has 64 divisors (see below), whose sum is σ = 54743040. Its totient is φ = 5123520.

The previous prime is 20974253. The next prime is 20974297. The reversal of 20974290 is 9247902.

It is not an unprimeable number, because it can be changed into a prime (20974297) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17077 + ... + 18263.

It is an arithmetic number, because the mean of its divisors is an integer number (855360).

Almost surely, 2^20974290 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20974290, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27371520).

20974290 is an abundant number, since it is smaller than the sum of its proper divisors (33768750).

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

20974290 is a wasteful number, since it uses less digits than its factorization.

20974290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1247.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20974290 is about 4579.7696448621. The cubic root of 20974290 is about 275.7797812774.

The spelling of 20974290 in words is "twenty million, nine hundred seventy-four thousand, two hundred ninety".