20921476 has 9 divisors (see below), whose sum is σ = 36628599. Its totient is φ = 10456164.

The previous prime is 20921449. The next prime is 20921479. The reversal of 20921476 is 67412902.

The square root of 20921476 is 4574.

It is a perfect power (a square), and thus also a powerful number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20921479) 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 2 ways as a sum of consecutive naturals, for example, 8005 + ... + 10291.

Almost surely, 2^20921476 is an apocalyptic number.

20921476 is the 4574-th square number.

It is an amenable number.

20921476 is a deficient number, since it is larger than the sum of its proper divisors (15707123).

20921476 is an frugal number, since it uses more digits than its factorization.

20921476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4578 (or 2289 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 31.

The cubic root of 20921476 is about 275.5481123216.

The spelling of 20921476 in words is "twenty million, nine hundred twenty-one thousand, four hundred seventy-six".