151638991 has 8 divisors (see below), whose sum is σ = 174060320. Its totient is φ = 129407328.

The previous prime is 151638979. The next prime is 151639003. The reversal of 151638991 is 199836151.

It is an interprime number because it is at equal distance from previous prime (151638979) and next prime (151639003).

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 151638991 - 2⁵ = 151638959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (151638901) 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, 45696 + ... + 48901.

It is an arithmetic number, because the mean of its divisors is an integer number (21757540).

Almost surely, 2^151638991 is an apocalyptic number.

151638991 is a deficient number, since it is larger than the sum of its proper divisors (22421329).

151638991 is an equidigital number, since it uses as much as digits as its factorization.

151638991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94833.

The product of its digits is 58320, while the sum is 43.

The square root of 151638991 is about 12314.1784541235. The cubic root of 151638991 is about 533.2574873480.

The spelling of 151638991 in words is "one hundred fifty-one million, six hundred thirty-eight thousand, nine hundred ninety-one".