20715986 has 8 divisors (see below), whose sum is σ = 31319040. Its totient is φ = 10276308.

The previous prime is 20715983. The next prime is 20715997. The reversal of 20715986 is 68951702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (20715983) 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, 40526 + ... + 41033.

It is an arithmetic number, because the mean of its divisors is an integer number (3914880).

Almost surely, 2^20715986 is an apocalyptic number.

20715986 is a deficient number, since it is larger than the sum of its proper divisors (10603054).

20715986 is a wasteful number, since it uses less digits than its factorization.

20715986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81688.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 20715986 is about 4551.4817367534. The cubic root of 20715986 is about 274.6430012156.

The spelling of 20715986 in words is "twenty million, seven hundred fifteen thousand, nine hundred eighty-six".