861431245 has 4 divisors (see below), whose sum is σ = 1033717500. Its totient is φ = 689144992.

The previous prime is 861431239. The next prime is 861431281. The reversal of 861431245 is 542134168.

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

It can be written as a sum of positive squares in 2 ways, for example, as 660387204 + 201044041 = 25698^2 + 14179^2 .

It is a cyclic number.

It is not a de Polignac number, because 861431245 - 2⁷ = 861431117 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 861431245.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86143120 + ... + 86143129.

It is an arithmetic number, because the mean of its divisors is an integer number (258429375).

Almost surely, 2^861431245 is an apocalyptic number.

It is an amenable number.

861431245 is a deficient number, since it is larger than the sum of its proper divisors (172286255).

861431245 is a wasteful number, since it uses less digits than its factorization.

861431245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172286254.

The product of its digits is 23040, while the sum is 34.

The square root of 861431245 is about 29350.1489774754. The cubic root of 861431245 is about 951.4957950343.

The spelling of 861431245 in words is "eight hundred sixty-one million, four hundred thirty-one thousand, two hundred forty-five".