21073313 has 8 divisors (see below), whose sum is σ = 22584768. Its totient is φ = 19611504.

The previous prime is 21073307. The next prime is 21073321. The reversal of 21073313 is 31337012.

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 a de Polignac number, because none of the positive numbers 2^k-21073313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21073363) 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, 11531 + ... + 13232.

It is an arithmetic number, because the mean of its divisors is an integer number (2823096).

Almost surely, 2^21073313 is an apocalyptic number.

21073313 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21073313 is a deficient number, since it is larger than the sum of its proper divisors (1511455).

21073313 is a wasteful number, since it uses less digits than its factorization.

21073313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24823.

The product of its (nonzero) digits is 378, while the sum is 20.

The square root of 21073313 is about 4590.5678298006. The cubic root of 21073313 is about 276.2131003177.

The spelling of 21073313 in words is "twenty-one million, seventy-three thousand, three hundred thirteen".