21300778 has 8 divisors (see below), whose sum is σ = 32021568. Its totient is φ = 10626924.

The previous prime is 21300757. The next prime is 21300791. The reversal of 21300778 is 87700312.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10576 + ... + 12427.

It is an arithmetic number, because the mean of its divisors is an integer number (4002696).

Almost surely, 2^21300778 is an apocalyptic number.

21300778 is a deficient number, since it is larger than the sum of its proper divisors (10720790).

21300778 is a wasteful number, since it uses less digits than its factorization.

21300778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23468.

The product of its (nonzero) digits is 2352, while the sum is 28.

The square root of 21300778 is about 4615.2765897614. The cubic root of 21300778 is about 277.2033591195.

The spelling of 21300778 in words is "twenty-one million, three hundred thousand, seven hundred seventy-eight".