861813651 has 8 divisors (see below), whose sum is σ = 1162929600. Its totient is φ = 567620072.

The previous prime is 861813629. The next prime is 861813661. The reversal of 861813651 is 156318168.

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

It is a cyclic number.

It is not a de Polignac number, because 861813651 - 2¹¹ = 861811603 is a prime.

It is not an unprimeable number, because it can be changed into a prime (861813661) 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, 1730301 + ... + 1730798.

It is an arithmetic number, because the mean of its divisors is an integer number (145366200).

Almost surely, 2^861813651 is an apocalyptic number.

861813651 is a deficient number, since it is larger than the sum of its proper divisors (301115949).

861813651 is a wasteful number, since it uses less digits than its factorization.

861813651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3461185.

The product of its digits is 34560, while the sum is 39.

The square root of 861813651 is about 29356.6628042085. The cubic root of 861813651 is about 951.6365700043.

The spelling of 861813651 in words is "eight hundred sixty-one million, eight hundred thirteen thousand, six hundred fifty-one".