20745797 has 12 divisors (see below), whose sum is σ = 22368420. Its totient is φ = 19173888.

The previous prime is 20745787. The next prime is 20745799. The reversal of 20745797 is 79754702.

It can be written as a sum of positive squares in 6 ways, for example, as 4351396 + 16394401 = 2086^2 + 4049^2 .

It is not a de Polignac number, because 20745797 - 2²⁰ = 19697221 is a prime.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20745799) 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, 90479 + ... + 90707.

It is an arithmetic number, because the mean of its divisors is an integer number (1864035).

Almost surely, 2^20745797 is an apocalyptic number.

It is an amenable number.

20745797 is a deficient number, since it is larger than the sum of its proper divisors (1622623).

20745797 is an equidigital number, since it uses as much as digits as its factorization.

20745797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 392 (or 319 counting only the distinct ones).

The product of its (nonzero) digits is 123480, while the sum is 41.

The square root of 20745797 is about 4554.7554270235. The cubic root of 20745797 is about 274.7746782425.

The spelling of 20745797 in words is "twenty million, seven hundred forty-five thousand, seven hundred ninety-seven".