20402408 has 16 divisors (see below), whose sum is σ = 41197380. Its totient is φ = 9416448.

The previous prime is 20402407. The next prime is 20402411. The reversal of 20402408 is 80420402.

It can be written as a sum of positive squares in 2 ways, for example, as 15984004 + 4418404 = 3998^2 + 2102^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20402408.

It is not an unprimeable number, because it can be changed into a prime (20402407) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97985 + ... + 98192.

Almost surely, 2^20402408 is an apocalyptic number.

It is an amenable number.

20402408 is an abundant number, since it is smaller than the sum of its proper divisors (20794972).

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

20402408 is a wasteful number, since it uses less digits than its factorization.

20402408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 196196 (or 196192 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 20402408 is about 4516.9024784691. The cubic root of 20402408 is about 273.2501921763.

The spelling of 20402408 in words is "twenty million, four hundred two thousand, four hundred eight".