21051364 has 6 divisors (see below), whose sum is σ = 36839894. Its totient is φ = 10525680.

The previous prime is 21051353. The next prime is 21051383. The reversal of 21051364 is 46315012.

It can be written as a sum of positive squares in only one way, i.e., 20884900 + 166464 = 4570^2 + 408^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2631417 + ... + 2631424.

Almost surely, 2^21051364 is an apocalyptic number.

It is an amenable number.

21051364 is a deficient number, since it is larger than the sum of its proper divisors (15788530).

21051364 is a wasteful number, since it uses less digits than its factorization.

21051364 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5262845 (or 5262843 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 21051364 is about 4588.1765441186. The cubic root of 21051364 is about 276.1171700226.

Adding to 21051364 its reverse (46315012), we get a palindrome (67366376).

The spelling of 21051364 in words is "twenty-one million, fifty-one thousand, three hundred sixty-four".