20974405 has 16 divisors (see below), whose sum is σ = 25683840. Its totient is φ = 16440768.

The previous prime is 20974381. The next prime is 20974409. The reversal of 20974405 is 50447902.

It is a cyclic number.

It is not a de Polignac number, because 20974405 - 2⁹ = 20973893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20974409) 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, 71439 + ... + 71731.

It is an arithmetic number, because the mean of its divisors is an integer number (1605240).

Almost surely, 2^20974405 is an apocalyptic number.

It is an amenable number.

20974405 is a deficient number, since it is larger than the sum of its proper divisors (4709435).

20974405 is a wasteful number, since it uses less digits than its factorization.

20974405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 20974405 is about 4579.7822000615. The cubic root of 20974405 is about 275.7802853011.

The spelling of 20974405 in words is "twenty million, nine hundred seventy-four thousand, four hundred five".