215400131 has 4 divisors (see below), whose sum is σ = 226737000. Its totient is φ = 204063264.

The previous prime is 215400079. The next prime is 215400137. The reversal of 215400131 is 131004512.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 215400131 - 2⁶ = 215400067 is a prime.

It is a super-2 number, since 2×215400131² = 92794432869634322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215400137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5668406 + ... + 5668443.

It is an arithmetic number, because the mean of its divisors is an integer number (56684250).

Almost surely, 2^215400131 is an apocalyptic number.

215400131 is a deficient number, since it is larger than the sum of its proper divisors (11336869).

215400131 is a wasteful number, since it uses less digits than its factorization.

215400131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11336868.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 215400131 is about 14676.5163100785. The cubic root of 215400131 is about 599.4440507673. Note that the first 3 decimals are identical.

Adding to 215400131 its reverse (131004512), we get a palindrome (346404643).

The spelling of 215400131 in words is "two hundred fifteen million, four hundred thousand, one hundred thirty-one".