20913485 has 24 divisors (see below), whose sum is σ = 27386856. Its totient is φ = 15319040.

The previous prime is 20913481. The next prime is 20913493. The reversal of 20913485 is 58431902.

It can be written as a sum of positive squares in 12 ways, for example, as 4761124 + 16152361 = 2182^2 + 4019^2 .

It is not a de Polignac number, because 20913485 - 2² = 20913481 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 (20913481) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 59069 + ... + 59421.

It is an arithmetic number, because the mean of its divisors is an integer number (1141119).

Almost surely, 2^20913485 is an apocalyptic number.

It is an amenable number.

20913485 is a deficient number, since it is larger than the sum of its proper divisors (6473371).

20913485 is a wasteful number, since it uses less digits than its factorization.

20913485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 433 (or 416 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 20913485 is about 4573.1263923054. The cubic root of 20913485 is about 275.5130258015.

The spelling of 20913485 in words is "twenty million, nine hundred thirteen thousand, four hundred eighty-five".