99991007 has 4 divisors (see below), whose sum is σ = 100025016. Its totient is φ = 99957000.

The previous prime is 99990973. The next prime is 99991009. The reversal of 99991007 is 70019999.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 99991007 - 2¹⁰ = 99989983 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 (99991009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12128 + ... + 18629.

It is an arithmetic number, because the mean of its divisors is an integer number (25006254).

Almost surely, 2^99991007 is an apocalyptic number.

99991007 is a deficient number, since it is larger than the sum of its proper divisors (34009).

99991007 is a wasteful number, since it uses less digits than its factorization.

99991007 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34008.

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

The square root of 99991007 is about 9999.5503398903. The cubic root of 99991007 is about 464.1449690080.

The spelling of 99991007 in words is "ninety-nine million, nine hundred ninety-one thousand, seven".