21485258 has 4 divisors (see below), whose sum is σ = 32227890. Its totient is φ = 10742628.

The previous prime is 21485249. The next prime is 21485267. The reversal of 21485258 is 85258412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21485249) and next prime (21485267).

It can be written as a sum of positive squares in only one way, i.e., 12201049 + 9284209 = 3493^2 + 3047^2 .

It is a super-2 number, since 2×21485258² = 923232622653128, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5371313 + ... + 5371316.

Almost surely, 2^21485258 is an apocalyptic number.

21485258 is a deficient number, since it is larger than the sum of its proper divisors (10742632).

21485258 is a wasteful number, since it uses less digits than its factorization.

21485258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10742631.

The product of its digits is 25600, while the sum is 35.

The square root of 21485258 is about 4635.2193044127. The cubic root of 21485258 is about 278.0013198012.

The spelling of 21485258 in words is "twenty-one million, four hundred eighty-five thousand, two hundred fifty-eight".