861640315 has 8 divisors (see below), whose sum is σ = 1069622640. Its totient is φ = 665542752.

The previous prime is 861640303. The next prime is 861640357. The reversal of 861640315 is 513046168.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 861640315 - 2¹⁹ = 861116027 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2971029 + ... + 2971318.

It is an arithmetic number, because the mean of its divisors is an integer number (133702830).

Almost surely, 2^861640315 is an apocalyptic number.

861640315 is a deficient number, since it is larger than the sum of its proper divisors (207982325).

861640315 is a wasteful number, since it uses less digits than its factorization.

861640315 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5942381.

The product of its (nonzero) digits is 17280, while the sum is 34.

The square root of 861640315 is about 29353.7104128252. The cubic root of 861640315 is about 951.5727650520.

The spelling of 861640315 in words is "eight hundred sixty-one million, six hundred forty thousand, three hundred fifteen".