20913525 has 24 divisors (see below), whose sum is σ = 38420160. Its totient is φ = 11153520.

The previous prime is 20913517. The next prime is 20913527. The reversal of 20913525 is 52531902.

It is not a de Polignac number, because 20913525 - 2³ = 20913517 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20913527) 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, 14817 + ... + 16166.

It is an arithmetic number, because the mean of its divisors is an integer number (1600840).

Almost surely, 2^20913525 is an apocalyptic number.

20913525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20913525 is a deficient number, since it is larger than the sum of its proper divisors (17506635).

20913525 is a wasteful number, since it uses less digits than its factorization.

20913525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31002 (or 30991 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 27.

The square root of 20913525 is about 4573.1307656790. The cubic root of 20913525 is about 275.5132014539.

The spelling of 20913525 in words is "twenty million, nine hundred thirteen thousand, five hundred twenty-five".