1068913721 has 4 divisors (see below), whose sum is σ = 1071994512. Its totient is φ = 1065832932.

The previous prime is 1068913711. The next prime is 1068913817. The reversal of 1068913721 is 1273198601.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1068913721 is a prime.

It is a super-2 number, since 2×1068913721² = 2285153085884131682, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1068913711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1539875 + ... + 1540568.

It is an arithmetic number, because the mean of its divisors is an integer number (267998628).

Almost surely, 2^1068913721 is an apocalyptic number.

It is an amenable number.

1068913721 is a deficient number, since it is larger than the sum of its proper divisors (3080791).

1068913721 is an equidigital number, since it uses as much as digits as its factorization.

1068913721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3080790.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 1068913721 is about 32694.2459922232. The cubic root of 1068913721 is about 1022.4628811875.

The spelling of 1068913721 in words is "one billion, sixty-eight million, nine hundred thirteen thousand, seven hundred twenty-one".