749276721 has 6 divisors (see below), whose sum is σ = 1082288610. Its totient is φ = 499517808.

The previous prime is 749276713. The next prime is 749276777. The reversal of 749276721 is 127672947.

It can be written as a sum of positive squares in only one way, i.e., 747749025 + 1527696 = 27345^2 + 1236^2 .

It is not a de Polignac number, because 749276721 - 2³ = 749276713 is a prime.

It is a super-2 number, since 2×749276721² = 1122831209265023682, which contains 22 as substring.

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

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (749277721) 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 5 ways as a sum of consecutive naturals, for example, 41626476 + ... + 41626493.

It is an arithmetic number, because the mean of its divisors is an integer number (180381435).

Almost surely, 2^749276721 is an apocalyptic number.

It is an amenable number.

749276721 is a deficient number, since it is larger than the sum of its proper divisors (333011889).

749276721 is a wasteful number, since it uses less digits than its factorization.

749276721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83252975 (or 83252972 counting only the distinct ones).

The product of its digits is 296352, while the sum is 45.

The square root of 749276721 is about 27372.9194825835. The cubic root of 749276721 is about 908.2681391098.

The spelling of 749276721 in words is "seven hundred forty-nine million, two hundred seventy-six thousand, seven hundred twenty-one".