20400484 has 24 divisors (see below), whose sum is σ = 38719800. Its totient is φ = 9348864.

The previous prime is 20400481. The next prime is 20400521. The reversal of 20400484 is 48400402.

It can be written as a sum of positive squares in 4 ways, for example, as 846400 + 19554084 = 920^2 + 4422^2 .

It is not an unprimeable number, because it can be changed into a prime (20400481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6432 + ... + 9064.

It is an arithmetic number, because the mean of its divisors is an integer number (1613325).

Almost surely, 2^20400484 is an apocalyptic number.

It is an amenable number.

20400484 is a deficient number, since it is larger than the sum of its proper divisors (18319316).

20400484 is a wasteful number, since it uses less digits than its factorization.

20400484 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2799 (or 2797 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 22.

The square root of 20400484 is about 4516.6894956373. The cubic root of 20400484 is about 273.2416025056.

Adding to 20400484 its reverse (48400402), we get a palindrome (68800886).

The spelling of 20400484 in words is "twenty million, four hundred thousand, four hundred eighty-four".