21330777 has 8 divisors (see below), whose sum is σ = 30628864. Its totient is φ = 13126608.

The previous prime is 21330761. The next prime is 21330781. The reversal of 21330777 is 77703312.

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

It is not a de Polignac number, because 21330777 - 2⁴ = 21330761 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21330737) 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, 273433 + ... + 273510.

It is an arithmetic number, because the mean of its divisors is an integer number (3828608).

Almost surely, 2^21330777 is an apocalyptic number.

It is an amenable number.

21330777 is a deficient number, since it is larger than the sum of its proper divisors (9298087).

21330777 is a wasteful number, since it uses less digits than its factorization.

21330777 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 546959.

The product of its (nonzero) digits is 6174, while the sum is 30.

The square root of 21330777 is about 4618.5254140256. The cubic root of 21330777 is about 277.3334314069. Note that the first 3 decimals are identical.

The spelling of 21330777 in words is "twenty-one million, three hundred thirty thousand, seven hundred seventy-seven".