21071458 has 16 divisors (see below), whose sum is σ = 33498360. Its totient is φ = 9923200.

The previous prime is 21071447. The next prime is 21071461. The reversal of 21071458 is 85417012.

It can be written as a sum of positive squares in 4 ways, for example, as 18948609 + 2122849 = 4353^2 + 1457^2 .

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, 2053 + ... + 6808.

Almost surely, 2^21071458 is an apocalyptic number.

21071458 is a deficient number, since it is larger than the sum of its proper divisors (12426902).

21071458 is a wasteful number, since it uses less digits than its factorization.

21071458 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8933.

The product of its (nonzero) digits is 2240, while the sum is 28.

The square root of 21071458 is about 4590.3657806323. The cubic root of 21071458 is about 276.2049954327.

The spelling of 21071458 in words is "twenty-one million, seventy-one thousand, four hundred fifty-eight".