746661781 has 4 divisors (see below), whose sum is σ = 749866572. Its totient is φ = 743456992.

The previous prime is 746661733. The next prime is 746661803. The reversal of 746661781 is 187166647.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 187166647 = 107 ⋅1749221.

It can be written as a sum of positive squares in 2 ways, for example, as 67798756 + 678863025 = 8234^2 + 26055^2 .

It is a cyclic number.

It is not a de Polignac number, because 746661781 - 2²⁵ = 713107349 is a prime.

It is a super-2 number, since 2×746661781² = 1115007630412183922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (746661481) 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 3 ways as a sum of consecutive naturals, for example, 1602046 + ... + 1602511.

It is an arithmetic number, because the mean of its divisors is an integer number (187466643).

Almost surely, 2^746661781 is an apocalyptic number.

It is an amenable number.

746661781 is a deficient number, since it is larger than the sum of its proper divisors (3204791).

746661781 is a wasteful number, since it uses less digits than its factorization.

746661781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3204790.

The product of its digits is 338688, while the sum is 46.

The square root of 746661781 is about 27325.1126438666. The cubic root of 746661781 is about 907.2103034010.

The spelling of 746661781 in words is "seven hundred forty-six million, six hundred sixty-one thousand, seven hundred eighty-one".