740406521 has 4 divisors (see below), whose sum is σ = 740461044. Its totient is φ = 740352000.

The previous prime is 740406487. The next prime is 740406523. The reversal of 740406521 is 125604047.

740406521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 686178025 + 54228496 = 26195^2 + 7364^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-740406521 is a prime.

It is a super-3 number, since 3×740406521³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (740406523) 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, 11141 + ... + 40061.

It is an arithmetic number, because the mean of its divisors is an integer number (185115261).

Almost surely, 2^740406521 is an apocalyptic number.

It is an amenable number.

740406521 is a deficient number, since it is larger than the sum of its proper divisors (54523).

740406521 is a wasteful number, since it uses less digits than its factorization.

740406521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54522.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 740406521 is about 27210.4119961459. The cubic root of 740406521 is about 904.6697699338.

The spelling of 740406521 in words is "seven hundred forty million, four hundred six thousand, five hundred twenty-one".