742781 has 8 divisors (see below), whose sum is σ = 847224. Its totient is φ = 645120.

The previous prime is 742759. The next prime is 742783. The reversal of 742781 is 187247.

It can be written as a sum of positive squares in 4 ways, for example, as 156025 + 586756 = 395^2 + 766^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 742781 - 2⁶ = 742717 is a prime.

It is a super-2 number, since 2×742781² = 1103447227922, which contains 22 as substring.

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 (742783) 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 7 ways as a sum of consecutive naturals, for example, 1460 + ... + 1901.

It is an arithmetic number, because the mean of its divisors is an integer number (105903).

2⁷⁴²⁷⁸¹ is an apocalyptic number.

It is an amenable number.

742781 is a deficient number, since it is larger than the sum of its proper divisors (104443).

742781 is a wasteful number, since it uses less digits than its factorization.

742781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3391.

The product of its digits is 3136, while the sum is 29.

The square root of 742781 is about 861.8474342945. The cubic root of 742781 is about 90.5635828019.

The spelling of 742781 in words is "seven hundred forty-two thousand, seven hundred eighty-one".