20702145 has 16 divisors (see below), whose sum is σ = 33299712. Its totient is φ = 10982400.

The previous prime is 20702131. The next prime is 20702147. The reversal of 20702145 is 54120702.

It is not a de Polignac number, because 20702145 - 2⁶ = 20702081 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20702147) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 681 + ... + 6470.

It is an arithmetic number, because the mean of its divisors is an integer number (2081232).

Almost surely, 2^20702145 is an apocalyptic number.

It is an amenable number.

20702145 is a deficient number, since it is larger than the sum of its proper divisors (12597567).

20702145 is a wasteful number, since it uses less digits than its factorization.

20702145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7352.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 20702145 is about 4549.9609888438. The cubic root of 20702145 is about 274.5818217205.

Adding to 20702145 its reverse (54120702), we get a palindrome (74822847).

The spelling of 20702145 in words is "twenty million, seven hundred two thousand, one hundred forty-five".