20400135 has 64 divisors (see below), whose sum is σ = 39398400. Its totient is φ = 8819712.

The previous prime is 20400101. The next prime is 20400151. The reversal of 20400135 is 53100402.

It is not a de Polignac number, because 20400135 - 2¹⁷ = 20269063 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 229171 + ... + 229259.

It is an arithmetic number, because the mean of its divisors is an integer number (615600).

Almost surely, 2^20400135 is an apocalyptic number.

20400135 is a deficient number, since it is larger than the sum of its proper divisors (18998265).

20400135 is a wasteful number, since it uses less digits than its factorization.

20400135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 200.

The product of its (nonzero) digits is 120, while the sum is 15.

The square root of 20400135 is about 4516.6508609810. The cubic root of 20400135 is about 273.2400443422.

Adding to 20400135 its reverse (53100402), we get a palindrome (73500537).

The spelling of 20400135 in words is "twenty million, four hundred thousand, one hundred thirty-five".