20702986 has 4 divisors (see below), whose sum is σ = 31054482. Its totient is φ = 10351492.

The previous prime is 20702971. The next prime is 20702987. The reversal of 20702986 is 68920702.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19971961 + 731025 = 4469^2 + 855^2 .

It is a super-2 number, since 2×20702986² = 857227258632392, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20702987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5175745 + ... + 5175748.

Almost surely, 2^20702986 is an apocalyptic number.

20702986 is a deficient number, since it is larger than the sum of its proper divisors (10351496).

20702986 is a wasteful number, since it uses less digits than its factorization.

20702986 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10351495.

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 20702986 is about 4550.0534062800. The cubic root of 20702986 is about 274.5855398567.

The spelling of 20702986 in words is "twenty million, seven hundred two thousand, nine hundred eighty-six".