861616331 has 2 divisors, whose sum is σ = 861616332. Its totient is φ = 861616330.

The previous prime is 861616319. The next prime is 861616369. The reversal of 861616331 is 133616168.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-861616331 is a prime.

It is a super-2 number, since 2×861616331² = 1484765403691803122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 861616291 and 861616300.

It is not a weakly prime, because it can be changed into another prime (861616631) 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 as a sum of consecutive naturals, namely, 430808165 + 430808166.

It is an arithmetic number, because the mean of its divisors is an integer number (430808166).

Almost surely, 2^861616331 is an apocalyptic number.

861616331 is a deficient number, since it is larger than the sum of its proper divisors (1).

861616331 is an equidigital number, since it uses as much as digits as its factorization.

861616331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15552, while the sum is 35.

The square root of 861616331 is about 29353.3018755983. The cubic root of 861616331 is about 951.5639358718.

The spelling of 861616331 in words is "eight hundred sixty-one million, six hundred sixteen thousand, three hundred thirty-one".