21280292 has 12 divisors (see below), whose sum is σ = 40626096. Its totient is φ = 9672840.

The previous prime is 21280289. The next prime is 21280307. The reversal of 21280292 is 29208212.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 241778 + ... + 241865.

It is an arithmetic number, because the mean of its divisors is an integer number (3385508).

Almost surely, 2^21280292 is an apocalyptic number.

21280292 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21280292 is a deficient number, since it is larger than the sum of its proper divisors (19345804).

21280292 is a wasteful number, since it uses less digits than its factorization.

21280292 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 483658 (or 483656 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 26.

The square root of 21280292 is about 4613.0566872736. The cubic root of 21280292 is about 277.1144639391.

The spelling of 21280292 in words is "twenty-one million, two hundred eighty thousand, two hundred ninety-two".