99866623 has 4 divisors (see below), whose sum is σ = 100246608. Its totient is φ = 99486640.

The previous prime is 99866609. The next prime is 99866651. The reversal of 99866623 is 32666899.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32666899 = 1867 ⋅17497.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99866623 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 (99866423) 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, 189598 + ... + 190123.

It is an arithmetic number, because the mean of its divisors is an integer number (25061652).

Almost surely, 2^99866623 is an apocalyptic number.

99866623 is a deficient number, since it is larger than the sum of its proper divisors (379985).

99866623 is a wasteful number, since it uses less digits than its factorization.

99866623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379984.

The product of its digits is 839808, while the sum is 49.

The square root of 99866623 is about 9993.3289248378. The cubic root of 99866623 is about 463.9524311495.

It can be divided in two parts, 99866 and 623, that added together give a square (100489 = 317²).

The spelling of 99866623 in words is "ninety-nine million, eight hundred sixty-six thousand, six hundred twenty-three".