21160791 has 8 divisors (see below), whose sum is σ = 31349360. Its totient is φ = 14107176.

The previous prime is 21160787. The next prime is 21160793. The reversal of 21160791 is 19706112.

It is not a de Polignac number, because 21160791 - 2² = 21160787 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 783733 = 21160791 / (2 + 1 + 1 + 6 + 0 + 7 + 9 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21160793) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 391840 + ... + 391893.

It is an arithmetic number, because the mean of its divisors is an integer number (3918670).

Almost surely, 2^21160791 is an apocalyptic number.

21160791 is a deficient number, since it is larger than the sum of its proper divisors (10188569).

21160791 is an equidigital number, since it uses as much as digits as its factorization.

21160791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 783742 (or 783736 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 27.

The square root of 21160791 is about 4600.0859774574. The cubic root of 21160791 is about 276.5947712414.

The spelling of 21160791 in words is "twenty-one million, one hundred sixty thousand, seven hundred ninety-one".