999151231 has 8 divisors (see below), whose sum is σ = 1076260304. Its totient is φ = 922078080.

The previous prime is 999151207. The next prime is 999151247. The reversal of 999151231 is 132151999.

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

It is a 7-Lehmer number, since φ(999151231) divides (999151231-1)⁷.

It is a cyclic number.

It is not a de Polignac number, because 999151231 - 2⁷ = 999151103 is a prime.

It is a super-2 number, since 2×999151231² = 1996606364817630722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999151201) 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, 86296 + ... + 97186.

It is an arithmetic number, because the mean of its divisors is an integer number (134532538).

Almost surely, 2^999151231 is an apocalyptic number.

999151231 is a deficient number, since it is larger than the sum of its proper divisors (77109073).

999151231 is a wasteful number, since it uses less digits than its factorization.

999151231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17961.

The product of its digits is 21870, while the sum is 40.

The square root of 999151231 is about 31609.3535365721. The cubic root of 999151231 is about 999.7169969168.

The spelling of 999151231 in words is "nine hundred ninety-nine million, one hundred fifty-one thousand, two hundred thirty-one".