21070259 has 16 divisors (see below), whose sum is σ = 26841600. Its totient is φ = 16101504.

The previous prime is 21070237. The next prime is 21070267. The reversal of 21070259 is 95207012.

21070259 = 171² + 172² + ... + 408².

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21070259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21070759) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2399 + ... + 6920.

It is an arithmetic number, because the mean of its divisors is an integer number (1677600).

Almost surely, 2^21070259 is an apocalyptic number.

21070259 is a deficient number, since it is larger than the sum of its proper divisors (5771341).

21070259 is a wasteful number, since it uses less digits than its factorization.

21070259 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9362.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 21070259 is about 4590.2351791602. The cubic root of 21070259 is about 276.1997564965.

The spelling of 21070259 in words is "twenty-one million, seventy thousand, two hundred fifty-nine".