100991951 has 8 divisors (see below), whose sum is σ = 107022384. Its totient is φ = 94971520.

The previous prime is 100991939. The next prime is 100991953. The reversal of 100991951 is 159199001.

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

It is not a de Polignac number, because 100991951 - 2⁶ = 100991887 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100991953) 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, 32036 + ... + 35046.

It is an arithmetic number, because the mean of its divisors is an integer number (13377798).

Almost surely, 2^100991951 is an apocalyptic number.

100991951 is a deficient number, since it is larger than the sum of its proper divisors (6030433).

100991951 is a wasteful number, since it uses less digits than its factorization.

100991951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5001.

The product of its (nonzero) digits is 3645, while the sum is 35.

The square root of 100991951 is about 10049.4751604250. The cubic root of 100991951 is about 465.6885794057.

The spelling of 100991951 in words is "one hundred million, nine hundred ninety-one thousand, nine hundred fifty-one".