21085092 has 54 divisors (see below), whose sum is σ = 62005398. Its totient is φ = 6023808.

The previous prime is 21085091. The next prime is 21085109. The reversal of 21085092 is 29058012.

It can be written as a sum of positive squares in only one way, i.e., 20575296 + 509796 = 4536^2 + 714^2 .

It is a super-2 number, since 2×21085092² = 889162209296928, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21085091) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4213 + ... + 7740.

Almost surely, 2^21085092 is an apocalyptic number.

It is an amenable number.

21085092 is an abundant number, since it is smaller than the sum of its proper divisors (40920306).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21085092 is a wasteful number, since it uses less digits than its factorization.

21085092 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11977 (or 11965 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 27.

The square root of 21085092 is about 4591.8506073260. The cubic root of 21085092 is about 276.2645541495.

The spelling of 21085092 in words is "twenty-one million, eighty-five thousand, ninety-two".