21141764 has 24 divisors (see below), whose sum is σ = 42389760. Its totient is φ = 9038016.

The previous prime is 21141751. The next prime is 21141779. The reversal of 21141764 is 46714112.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15269 + ... + 16595.

It is an arithmetic number, because the mean of its divisors is an integer number (1766240).

Almost surely, 2^21141764 is an apocalyptic number.

It is an amenable number.

21141764 is an abundant number, since it is smaller than the sum of its proper divisors (21247996).

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

21141764 is a wasteful number, since it uses less digits than its factorization.

21141764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1907 (or 1905 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 21141764 is about 4598.0173988362. The cubic root of 21141764 is about 276.5118451217.

Adding to 21141764 its reverse (46714112), we get a palindrome (67855876).

The spelling of 21141764 in words is "twenty-one million, one hundred forty-one thousand, seven hundred sixty-four".