20399376 has 40 divisors (see below), whose sum is σ = 53569984. Its totient is φ = 6687360.

The previous prime is 20399359. The next prime is 20399389. The reversal of 20399376 is 67399302.

It is a super-2 number, since 2×20399376² = 832269082378752, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 556 + ... + 6411.

Almost surely, 2^20399376 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20399376, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26784992).

20399376 is an abundant number, since it is smaller than the sum of its proper divisors (33170608).

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

20399376 is a wasteful number, since it uses less digits than its factorization.

20399376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7039 (or 7033 counting only the distinct ones).

The product of its (nonzero) digits is 61236, while the sum is 39.

The square root of 20399376 is about 4516.5668377652. The cubic root of 20399376 is about 273.2366556103.

The spelling of 20399376 in words is "twenty million, three hundred ninety-nine thousand, three hundred seventy-six".