20451404 has 6 divisors (see below), whose sum is σ = 35789964. Its totient is φ = 10225700.

The previous prime is 20451397. The next prime is 20451407. The reversal of 20451404 is 40415402.

It is not an unprimeable number, because it can be changed into a prime (20451407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2556422 + ... + 2556429.

It is an arithmetic number, because the mean of its divisors is an integer number (5964994).

Almost surely, 2^20451404 is an apocalyptic number.

It is an amenable number.

20451404 is a deficient number, since it is larger than the sum of its proper divisors (15338560).

20451404 is a wasteful number, since it uses less digits than its factorization.

20451404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5112855 (or 5112853 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 20451404 is about 4522.3228544632. The cubic root of 20451404 is about 273.4687523833.

Adding to 20451404 its reverse (40415402), we get a palindrome (60866806).

The spelling of 20451404 in words is "twenty million, four hundred fifty-one thousand, four hundred four".