721213734 has 16 divisors (see below), whose sum is σ = 1443108672. Its totient is φ = 240291048.

The previous prime is 721213693. The next prime is 721213741. The reversal of 721213734 is 437312127.

It is a super-2 number, since 2×721213734² = 1040298500220445512, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 14064 + ... + 40499.

It is an arithmetic number, because the mean of its divisors is an integer number (90194292).

Almost surely, 2^721213734 is an apocalyptic number.

721213734 is an abundant number, since it is smaller than the sum of its proper divisors (721894938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721213734 is a wasteful number, since it uses less digits than its factorization.

721213734 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56771.

The product of its digits is 7056, while the sum is 30.

The square root of 721213734 is about 26855.4228043425. The cubic root of 721213734 is about 896.7842992917.

It can be divided in two parts, 72121 and 3734, that added together give a triangular number (75855 = T₃₈₉).

The spelling of 721213734 in words is "seven hundred twenty-one million, two hundred thirteen thousand, seven hundred thirty-four".