21700258 has 8 divisors (see below), whose sum is σ = 32886252. Its totient is φ = 10738176.

The previous prime is 21700253. The next prime is 21700291. The reversal of 21700258 is 85200712.

It can be written as a sum of positive squares in 2 ways, for example, as 20277009 + 1423249 = 4503^2 + 1193^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (21700253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55735 + ... + 56122.

Almost surely, 2^21700258 is an apocalyptic number.

21700258 is a deficient number, since it is larger than the sum of its proper divisors (11185994).

21700258 is a wasteful number, since it uses less digits than its factorization.

21700258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111956.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 21700258 is about 4658.3535718105. The cubic root of 21700258 is about 278.9255506360.

The spelling of 21700258 in words is "twenty-one million, seven hundred thousand, two hundred fifty-eight".