19713987 has 12 divisors (see below), whose sum is σ = 28622880. Its totient is φ = 13074768.

The previous prime is 19713961. The next prime is 19714003. The reversal of 19713987 is 78931791.

It is not a de Polignac number, because 19713987 - 2⁸ = 19713731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19713917) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3787 + ... + 7332.

It is an arithmetic number, because the mean of its divisors is an integer number (2385240).

Almost surely, 2^19713987 is an apocalyptic number.

19713987 is a deficient number, since it is larger than the sum of its proper divisors (8908893).

19713987 is a wasteful number, since it uses less digits than its factorization.

19713987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11322 (or 11319 counting only the distinct ones).

The product of its digits is 95256, while the sum is 45.

The square root of 19713987 is about 4440.0435808672. The cubic root of 19713987 is about 270.1416129549.

The spelling of 19713987 in words is "nineteen million, seven hundred thirteen thousand, nine hundred eighty-seven".