21012299 has 8 divisors (see below), whose sum is σ = 26197248. Its totient is φ = 16373160.

The previous prime is 21012283. The next prime is 21012301. The reversal of 21012299 is 99221012.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21012299 - 2⁴ = 21012283 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21012239) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136367 + ... + 136520.

It is an arithmetic number, because the mean of its divisors is an integer number (3274656).

Almost surely, 2^21012299 is an apocalyptic number.

21012299 is a deficient number, since it is larger than the sum of its proper divisors (5184949).

21012299 is a wasteful number, since it uses less digits than its factorization.

21012299 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272905.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 21012299 is about 4583.9174294483. The cubic root of 21012299 is about 275.9462674577.

The spelling of 21012299 in words is "twenty-one million, twelve thousand, two hundred ninety-nine".