20400601 has 16 divisors (see below), whose sum is σ = 23178960. Its totient is φ = 17821440.

The previous prime is 20400599. The next prime is 20400631. The reversal of 20400601 is 10600402.

It can be written as a sum of positive squares in 8 ways, for example, as 15376 + 20385225 = 124^2 + 4515^2 .

It is not a de Polignac number, because 20400601 - 2¹ = 20400599 is a prime.

It is a super-2 number, since 2×20400601² = 832369042322402, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20400631) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19471 + ... + 20491.

It is an arithmetic number, because the mean of its divisors is an integer number (1448685).

Almost surely, 2^20400601 is an apocalyptic number.

It is an amenable number.

20400601 is a deficient number, since it is larger than the sum of its proper divisors (2778359).

20400601 is a wasteful number, since it uses less digits than its factorization.

20400601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1116.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 20400601 is about 4516.7024475827. The cubic root of 20400601 is about 273.2421248658.

The spelling of 20400601 in words is "twenty million, four hundred thousand, six hundred one".