21229090 has 32 divisors (see below), whose sum is σ = 40777344. Its totient is φ = 7929600.

The previous prime is 21229063. The next prime is 21229111. The reversal of 21229090 is 9092212.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25257 + ... + 26083.

It is an arithmetic number, because the mean of its divisors is an integer number (1274292).

Almost surely, 2^21229090 is an apocalyptic number.

21229090 is a deficient number, since it is larger than the sum of its proper divisors (19548254).

21229090 is a wasteful number, since it uses less digits than its factorization.

21229090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 21229090 is about 4607.5036625053. The cubic root of 21229090 is about 276.8920326271.

The spelling of 21229090 in words is "twenty-one million, two hundred twenty-nine thousand, ninety".