20399274 has 48 divisors (see below), whose sum is σ = 53177280. Its totient is φ = 5520960.

The previous prime is 20399261. The next prime is 20399279. The reversal of 20399274 is 47299302.

It is a super-2 number, since 2×20399274² = 832260759454152, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20399279) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1867 + ... + 6654.

It is an arithmetic number, because the mean of its divisors is an integer number (1107860).

Almost surely, 2^20399274 is an apocalyptic number.

20399274 is an abundant number, since it is smaller than the sum of its proper divisors (32778006).

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

20399274 is a wasteful number, since it uses less digits than its factorization.

20399274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8555 (or 8552 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 20399274 is about 4516.5555459886. Note that the first 4 decimals coincide. The cubic root of 20399274 is about 273.2362002011.

The spelling of 20399274 in words is "twenty million, three hundred ninety-nine thousand, two hundred seventy-four".