20399076 has 36 divisors (see below), whose sum is σ = 52193232. Its totient is φ = 6716784.

The previous prime is 20399059. The next prime is 20399087. The reversal of 20399076 is 67099302.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×20399076² = 832244603307552, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 20399076.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 426 + ... + 6401.

It is an arithmetic number, because the mean of its divisors is an integer number (1449812).

Almost surely, 2^20399076 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 20399076, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26096616).

20399076 is an abundant number, since it is smaller than the sum of its proper divisors (31794156).

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

20399076 is a wasteful number, since it uses less digits than its factorization.

20399076 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6920 (or 6915 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 36.

The square root of 20399076 is about 4516.5336265769. The cubic root of 20399076 is about 273.2353161674.

The spelling of 20399076 in words is "twenty million, three hundred ninety-nine thousand, seventy-six".