20987004 has 48 divisors (see below), whose sum is σ = 50577408. Its totient is φ = 6769728.

The previous prime is 20986991. The next prime is 20987023. The reversal of 20987004 is 40078902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71482 + ... + 71774.

It is an arithmetic number, because the mean of its divisors is an integer number (1053696).

Almost surely, 2^20987004 is an apocalyptic number.

It is an amenable number.

20987004 is an abundant number, since it is smaller than the sum of its proper divisors (29590404).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20987004 is a wasteful number, since it uses less digits than its factorization.

20987004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 20987004 is about 4581.1574956554. The cubic root of 20987004 is about 275.8354932294.

The spelling of 20987004 in words is "twenty million, nine hundred eighty-seven thousand, four".