861597831 has 8 divisors (see below), whose sum is σ = 1149021424. Its totient is φ = 574286400.

The previous prime is 861597817. The next prime is 861597833. The reversal of 861597831 is 138795168.

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

It is not a de Polignac number, because 861597831 - 2¹³ = 861589639 is a prime.

It is a super-2 number, since 2×861597831² = 1484701644767809122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861597833) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8086 + ... + 42291.

It is an arithmetic number, because the mean of its divisors is an integer number (143627678).

Almost surely, 2^861597831 is an apocalyptic number.

861597831 is a deficient number, since it is larger than the sum of its proper divisors (287423593).

861597831 is a wasteful number, since it uses less digits than its factorization.

861597831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56081.

The product of its digits is 362880, while the sum is 48.

The square root of 861597831 is about 29352.9867475186. The cubic root of 861597831 is about 951.5571253932.

The spelling of 861597831 in words is "eight hundred sixty-one million, five hundred ninety-seven thousand, eight hundred thirty-one".