861251603 has 16 divisors (see below), whose sum is σ = 924231744. Its totient is φ = 799718400.

The previous prime is 861251597. The next prime is 861251621. The reversal of 861251603 is 306152168.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 861251603 - 2⁶ = 861251539 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 861251603.

It is not an unprimeable number, because it can be changed into a prime (861251653) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 401951 + ... + 404087.

It is an arithmetic number, because the mean of its divisors is an integer number (57764484).

Almost surely, 2^861251603 is an apocalyptic number.

861251603 is a deficient number, since it is larger than the sum of its proper divisors (62980141).

861251603 is a wasteful number, since it uses less digits than its factorization.

861251603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2462.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 861251603 is about 29347.0884927279. The cubic root of 861251603 is about 951.4296491127.

The spelling of 861251603 in words is "eight hundred sixty-one million, two hundred fifty-one thousand, six hundred three".