20765915 has 4 divisors (see below), whose sum is σ = 24919104. Its totient is φ = 16612728.

The previous prime is 20765909. The next prime is 20765923. The reversal of 20765915 is 51956702.

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

It is a cyclic number.

It is not a de Polignac number, because 20765915 - 2⁶ = 20765851 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2076587 + ... + 2076596.

It is an arithmetic number, because the mean of its divisors is an integer number (6229776).

Almost surely, 2^20765915 is an apocalyptic number.

20765915 is a deficient number, since it is larger than the sum of its proper divisors (4153189).

20765915 is an equidigital number, since it uses as much as digits as its factorization.

20765915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4153188.

The product of its (nonzero) digits is 18900, while the sum is 35.

The square root of 20765915 is about 4556.9633529358. The cubic root of 20765915 is about 274.8634694173.

The spelling of 20765915 in words is "twenty million, seven hundred sixty-five thousand, nine hundred fifteen".