20912407 has 4 divisors (see below), whose sum is σ = 22013080. Its totient is φ = 19811736.

The previous prime is 20912377. The next prime is 20912417. The reversal of 20912407 is 70421902.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 70421902 = 2 ⋅35210951.

It is a cyclic number.

It is not a de Polignac number, because 20912407 - 2¹⁹ = 20388119 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20912417) 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, 550308 + ... + 550345.

It is an arithmetic number, because the mean of its divisors is an integer number (5503270).

Almost surely, 2^20912407 is an apocalyptic number.

20912407 is a deficient number, since it is larger than the sum of its proper divisors (1100673).

20912407 is a wasteful number, since it uses less digits than its factorization.

20912407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100672.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 20912407 is about 4573.0085283104. The cubic root of 20912407 is about 275.5082918839.

The spelling of 20912407 in words is "twenty million, nine hundred twelve thousand, four hundred seven".