21776099 has 4 divisors (see below), whose sum is σ = 23057064. Its totient is φ = 20495136.

The previous prime is 21776081. The next prime is 21776123. The reversal of 21776099 is 99067712.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21776099 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21776039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 640457 + ... + 640490.

It is an arithmetic number, because the mean of its divisors is an integer number (5764266).

Almost surely, 2^21776099 is an apocalyptic number.

21776099 is a deficient number, since it is larger than the sum of its proper divisors (1280965).

21776099 is a wasteful number, since it uses less digits than its factorization.

21776099 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1280964.

The product of its (nonzero) digits is 47628, while the sum is 41.

The square root of 21776099 is about 4666.4867941525. The cubic root of 21776099 is about 279.2501150794.

The spelling of 21776099 in words is "twenty-one million, seven hundred seventy-six thousand, ninety-nine".