749393621 has 4 divisors (see below), whose sum is σ = 749457600. Its totient is φ = 749329644.

The previous prime is 749393591. The next prime is 749393647. The reversal of 749393621 is 126393947.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 749393621 - 2¹⁰ = 749392597 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (749393681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8831 + ... + 39708.

It is an arithmetic number, because the mean of its divisors is an integer number (187364400).

Almost surely, 2^749393621 is an apocalyptic number.

It is an amenable number.

749393621 is a deficient number, since it is larger than the sum of its proper divisors (63979).

749393621 is a wasteful number, since it uses less digits than its factorization.

749393621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63978.

The product of its digits is 244944, while the sum is 44.

The square root of 749393621 is about 27375.0547214065. The cubic root of 749393621 is about 908.3153717815.

The spelling of 749393621 in words is "seven hundred forty-nine million, three hundred ninety-three thousand, six hundred twenty-one".