91999007 has 8 divisors (see below), whose sum is σ = 97494000. Its totient is φ = 86569344.

The previous prime is 91998961. The next prime is 91999009. The reversal of 91999007 is 70099919.

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 91999007 - 2¹² = 91994911 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 (91999009) 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, 13418 + ... + 19079.

It is an arithmetic number, because the mean of its divisors is an integer number (12186750).

Almost surely, 2^91999007 is an apocalyptic number.

91999007 is a deficient number, since it is larger than the sum of its proper divisors (5494993).

91999007 is a wasteful number, since it uses less digits than its factorization.

91999007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32665.

The product of its (nonzero) digits is 45927, while the sum is 44.

The square root of 91999007 is about 9591.6112827825. The cubic root of 91999007 is about 451.4341193543.

The spelling of 91999007 in words is "ninety-one million, nine hundred ninety-nine thousand, seven".