21076747 has 8 divisors (see below), whose sum is σ = 21959280. Its totient is φ = 20211840.

The previous prime is 21076739. The next prime is 21076789. The reversal of 21076747 is 74767012.

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 21076747 - 2³ = 21076739 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21076147) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1938 + ... + 6775.

It is an arithmetic number, because the mean of its divisors is an integer number (2744910).

Almost surely, 2^21076747 is an apocalyptic number.

21076747 is a deficient number, since it is larger than the sum of its proper divisors (882533).

21076747 is an equidigital number, since it uses as much as digits as its factorization.

21076747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8813.

The product of its (nonzero) digits is 16464, while the sum is 34.

The square root of 21076747 is about 4590.9418423674. The cubic root of 21076747 is about 276.2281029305.

The spelling of 21076747 in words is "twenty-one million, seventy-six thousand, seven hundred forty-seven".