20924487 has 14 divisors (see below), whose sum is σ = 31373472. Its totient is φ = 13949172.

The previous prime is 20924483. The next prime is 20924509. The reversal of 20924487 is 78442902.

20924487 is a `hidden beast` number, since 209 + 2 + 448 + 7 = 666.

It is not a de Polignac number, because 20924487 - 2² = 20924483 is a prime.

It is a nialpdrome in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20924483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 13623 + ... + 15080.

Almost surely, 2^20924487 is an apocalyptic number.

20924487 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

20924487 is a deficient number, since it is larger than the sum of its proper divisors (10448985).

20924487 is an frugal number, since it uses more digits than its factorization.

20924487 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28721 (or 28706 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 20924487 is about 4574.3291311404. The cubic root of 20924487 is about 275.5613305663.

The spelling of 20924487 in words is "twenty million, nine hundred twenty-four thousand, four hundred eighty-seven".