99963591 has 16 divisors (see below), whose sum is σ = 164043264. Its totient is φ = 52727904.

The previous prime is 99963581. The next prime is 99963593. The reversal of 99963591 is 19536999.

It is not a de Polignac number, because 99963591 - 2⁷ = 99963463 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (99963593) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 182811 + ... + 183356.

It is an arithmetic number, because the mean of its divisors is an integer number (10252704).

Almost surely, 2^99963591 is an apocalyptic number.

99963591 is a gapful number since it is divisible by the number (91) formed by its first and last digit.

99963591 is a deficient number, since it is larger than the sum of its proper divisors (64079673).

99963591 is a wasteful number, since it uses less digits than its factorization.

99963591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366190.

The product of its digits is 590490, while the sum is 51.

The square root of 99963591 is about 9998.1793842679. The cubic root of 99963591 is about 464.1025446540.

The spelling of 99963591 in words is "ninety-nine million, nine hundred sixty-three thousand, five hundred ninety-one".