99990691 has 4 divisors (see below), whose sum is σ = 100011384. Its totient is φ = 99970000.

The previous prime is 99990679. The next prime is 99990703. The reversal of 99990691 is 19609999.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19609999 = 743 ⋅26393.

It is an interprime number because it is at equal distance from previous prime (99990679) and next prime (99990703).

It is a cyclic number.

It is not a de Polignac number, because 99990691 - 2¹³ = 99982499 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (99990641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1191 + ... + 14191.

It is an arithmetic number, because the mean of its divisors is an integer number (25002846).

Almost surely, 2^99990691 is an apocalyptic number.

99990691 is a deficient number, since it is larger than the sum of its proper divisors (20693).

99990691 is a wasteful number, since it uses less digits than its factorization.

99990691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20692.

The product of its (nonzero) digits is 354294, while the sum is 52.

The square root of 99990691 is about 9999.5345391673. The cubic root of 99990691 is about 464.1444800642.

The spelling of 99990691 in words is "ninety-nine million, nine hundred ninety thousand, six hundred ninety-one".