19887995 has 4 divisors (see below), whose sum is σ = 23865600. Its totient is φ = 15910392.

The previous prime is 19887979. The next prime is 19888021. The reversal of 19887995 is 59978891.

It is a happy number.

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 19887995 - 2⁴ = 19887979 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19887995.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1988795 + ... + 1988804.

It is an arithmetic number, because the mean of its divisors is an integer number (5966400).

Almost surely, 2^19887995 is an apocalyptic number.

19887995 is a deficient number, since it is larger than the sum of its proper divisors (3977605).

19887995 is an equidigital number, since it uses as much as digits as its factorization.

19887995 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3977604.

The product of its digits is 1632960, while the sum is 56.

The square root of 19887995 is about 4459.5958337051. The cubic root of 19887995 is about 270.9340988887.

The spelling of 19887995 in words is "nineteen million, eight hundred eighty-seven thousand, nine hundred ninety-five".