20831445 has 32 divisors (see below), whose sum is σ = 38649600. Its totient is φ = 10625472.

The previous prime is 20831323. The next prime is 20831533. The reversal of 20831445 is 54413802.

It is not a de Polignac number, because 20831445 - 2¹⁰ = 20830421 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 250 + ... + 6459.

It is an arithmetic number, because the mean of its divisors is an integer number (1207800).

Almost surely, 2^20831445 is an apocalyptic number.

It is an amenable number.

20831445 is a deficient number, since it is larger than the sum of its proper divisors (17818155).

20831445 is a wasteful number, since it uses less digits than its factorization.

20831445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6746 (or 6740 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 27.

The square root of 20831445 is about 4564.1477846363. The cubic root of 20831445 is about 275.1522903043.

The spelling of 20831445 in words is "twenty million, eight hundred thirty-one thousand, four hundred forty-five".