20400004 has 24 divisors (see below), whose sum is σ = 36590400. Its totient is φ = 9948960.

The previous prime is 20399993. The next prime is 20400013. The reversal of 20400004 is 40000402.

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, 30627 + ... + 31285.

It is an arithmetic number, because the mean of its divisors is an integer number (1524600).

Almost surely, 2^20400004 is an apocalyptic number.

It is an amenable number.

20400004 is a deficient number, since it is larger than the sum of its proper divisors (16190396).

20400004 is a wasteful number, since it uses less digits than its factorization.

20400004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 843 (or 841 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 10.

The square root of 20400004 is about 4516.6363590619. The cubic root of 20400004 is about 273.2394594682.

Adding to 20400004 its reverse (40000402), we get a palindrome (60400406).

The spelling of 20400004 in words is "twenty million, four hundred thousand, four".