861138951 has 8 divisors (see below), whose sum is σ = 1150007424. Its totient is φ = 573181560.

The previous prime is 861138931. The next prime is 861138959. The reversal of 861138951 is 159831168.

861138951 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 861138951 - 2⁷ = 861138823 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861138959) 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, 225561 + ... + 229346.

It is an arithmetic number, because the mean of its divisors is an integer number (143750928).

Almost surely, 2^861138951 is an apocalyptic number.

861138951 is a deficient number, since it is larger than the sum of its proper divisors (288868473).

861138951 is a wasteful number, since it uses less digits than its factorization.

861138951 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 455541.

The product of its digits is 51840, while the sum is 42.

The square root of 861138951 is about 29345.1691254285. The cubic root of 861138951 is about 951.3881648643.

The spelling of 861138951 in words is "eight hundred sixty-one million, one hundred thirty-eight thousand, nine hundred fifty-one".