99404639 has 2 divisors, whose sum is σ = 99404640. Its totient is φ = 99404638.

The previous prime is 99404633. The next prime is 99404647. The reversal of 99404639 is 93640499.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (93640499) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-99404639 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 99404639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99404633) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49702319 + 49702320.

It is an arithmetic number, because the mean of its divisors is an integer number (49702320).

Almost surely, 2^99404639 is an apocalyptic number.

99404639 is a deficient number, since it is larger than the sum of its proper divisors (1).

99404639 is an equidigital number, since it uses as much as digits as its factorization.

99404639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 209952, while the sum is 44.

The square root of 99404639 is about 9970.1875107743. The cubic root of 99404639 is about 463.2359089309.

The spelling of 99404639 in words is "ninety-nine million, four hundred four thousand, six hundred thirty-nine".