20487915 has 48 divisors (see below), whose sum is σ = 40916928. Its totient is φ = 9289728.

The previous prime is 20487893. The next prime is 20487919. The reversal of 20487915 is 51978402.

It is not a de Polignac number, because 20487915 - 2⁷ = 20487787 is a prime.

It is a super-2 number, since 2×20487915² = 839509322094450, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20487915.

It is not an unprimeable number, because it can be changed into a prime (20487919) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 60627 + ... + 60963.

It is an arithmetic number, because the mean of its divisors is an integer number (852436).

Almost surely, 2^20487915 is an apocalyptic number.

20487915 is a deficient number, since it is larger than the sum of its proper divisors (20429013).

20487915 is a wasteful number, since it uses less digits than its factorization.

20487915 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 548 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 36.

The square root of 20487915 is about 4526.3578073325. The cubic root of 20487915 is about 273.6313929173.

The spelling of 20487915 in words is "twenty million, four hundred eighty-seven thousand, nine hundred fifteen".