21256292 has 6 divisors (see below), whose sum is σ = 37198518. Its totient is φ = 10628144.

The previous prime is 21256283. The next prime is 21256303. The reversal of 21256292 is 29265212.

It can be written as a sum of positive squares in only one way, i.e., 20124196 + 1132096 = 4486^2 + 1064^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2657033 + ... + 2657040.

It is an arithmetic number, because the mean of its divisors is an integer number (6199753).

Almost surely, 2^21256292 is an apocalyptic number.

It is an amenable number.

21256292 is a deficient number, since it is larger than the sum of its proper divisors (15942226).

21256292 is a wasteful number, since it uses less digits than its factorization.

21256292 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5314077 (or 5314075 counting only the distinct ones).

The product of its digits is 4320, while the sum is 29.

The square root of 21256292 is about 4610.4546413559. The cubic root of 21256292 is about 277.0102478104.

The spelling of 21256292 in words is "twenty-one million, two hundred fifty-six thousand, two hundred ninety-two".