20243915 has 4 divisors (see below), whose sum is σ = 24292704. Its totient is φ = 16195128.

The previous prime is 20243891. The next prime is 20243939. The reversal of 20243915 is 51934202.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 51934202 = 2 ⋅25967101.

It is an interprime number because it is at equal distance from previous prime (20243891) and next prime (20243939).

It is a cyclic number.

It is not a de Polignac number, because 20243915 - 2⁸ = 20243659 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, 2024387 + ... + 2024396.

It is an arithmetic number, because the mean of its divisors is an integer number (6073176).

Almost surely, 2^20243915 is an apocalyptic number.

20243915 is a deficient number, since it is larger than the sum of its proper divisors (4048789).

20243915 is an equidigital number, since it uses as much as digits as its factorization.

20243915 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4048788.

The product of its (nonzero) digits is 2160, while the sum is 26.

The square root of 20243915 is about 4499.3238380895. The cubic root of 20243915 is about 272.5407845136.

The spelling of 20243915 in words is "twenty million, two hundred forty-three thousand, nine hundred fifteen".