861552945 has 96 divisors (see below), whose sum is σ = 1765805184. Its totient is φ = 383846400.

The previous prime is 861552919. The next prime is 861552953. The reversal of 861552945 is 549255168.

861552945 is a `hidden beast` number, since 8 + 6 + 1 + 552 + 94 + 5 = 666.

It is not a de Polignac number, because 861552945 - 2⁸ = 861552689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 861552945.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 360655 + ... + 363035.

It is an arithmetic number, because the mean of its divisors is an integer number (18393804).

Almost surely, 2^861552945 is an apocalyptic number.

861552945 is a gapful number since it is divisible by the number (85) formed by its first and last digit.

It is an amenable number.

861552945 is an abundant number, since it is smaller than the sum of its proper divisors (904252239).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

861552945 is a wasteful number, since it uses less digits than its factorization.

861552945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2463 (or 2460 counting only the distinct ones).

The product of its digits is 432000, while the sum is 45.

The square root of 861552945 is about 29352.2221475649. Note that the first 3 decimals coincide. The cubic root of 861552945 is about 951.5406009261.

The spelling of 861552945 in words is "eight hundred sixty-one million, five hundred fifty-two thousand, nine hundred forty-five".