215790131 has 4 divisors (see below), whose sum is σ = 223231200. Its totient is φ = 208349064.

The previous prime is 215790119. The next prime is 215790151. The reversal of 215790131 is 131097512.

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 215790131 - 2⁶ = 215790067 is a prime.

It is a super-2 number, since 2×215790131² = 93130761273994322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 7441039 = 215790131 / (2 + 1 + 5 + 7 + 9 + 0 + 1 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 215790094 and 215790103.

It is not an unprimeable number, because it can be changed into a prime (215790151) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3720491 + ... + 3720548.

It is an arithmetic number, because the mean of its divisors is an integer number (55807800).

Almost surely, 2^215790131 is an apocalyptic number.

215790131 is a deficient number, since it is larger than the sum of its proper divisors (7441069).

215790131 is an equidigital number, since it uses as much as digits as its factorization.

215790131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7441068.

The product of its (nonzero) digits is 1890, while the sum is 29.

The square root of 215790131 is about 14689.7968331764. The cubic root of 215790131 is about 599.8056138820.

The spelling of 215790131 in words is "two hundred fifteen million, seven hundred ninety thousand, one hundred thirty-one".