20702137 has 4 divisors (see below), whose sum is σ = 21142656. Its totient is φ = 20261620.

The previous prime is 20702131. The next prime is 20702147. The reversal of 20702137 is 73120702.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20702137 - 2⁷ = 20702009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20702131) 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, 220189 + ... + 220282.

It is an arithmetic number, because the mean of its divisors is an integer number (5285664).

Almost surely, 2^20702137 is an apocalyptic number.

It is an amenable number.

20702137 is a deficient number, since it is larger than the sum of its proper divisors (440519).

20702137 is an equidigital number, since it uses as much as digits as its factorization.

20702137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440518.

The product of its (nonzero) digits is 588, while the sum is 22.

The square root of 20702137 is about 4549.9601097152. The cubic root of 20702137 is about 274.5817863513.

Adding to 20702137 its reverse (73120702), we get a palindrome (93822839).

The spelling of 20702137 in words is "twenty million, seven hundred two thousand, one hundred thirty-seven".