3157729 has 3 divisors (see below), whose sum is σ = 3159507. Its totient is φ = 3155952.

The previous prime is 3157711. The next prime is 3157751. The reversal of 3157729 is 9277513.

The square root of 3157729 is 1777.

It is a perfect power (a square), and thus also a powerful number.

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 only one way, i.e., 1600225 + 1557504 = 1265^2 + 1248^2 .

It is not a de Polignac number, because 3157729 - 2¹³ = 3149537 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 3157694 and 3157703.

It is not an unprimeable number, because it can be changed into a prime (3157229) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 889 + ... + 2665.

It is an arithmetic number, because the mean of its divisors is an integer number (1053169).

Almost surely, 2^3157729 is an apocalyptic number.

3157729 is the 1777-th square number.

3157729 is the 889-th centered octagonal number.

It is an amenable number.

3157729 is a deficient number, since it is larger than the sum of its proper divisors (1778).

3157729 is an frugal number, since it uses more digits than its factorization.

3157729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3554 (or 1777 counting only the distinct ones).

The product of its digits is 13230, while the sum is 34.

The cubic root of 3157729 is about 146.7095162908.

The spelling of 3157729 in words is "three million, one hundred fifty-seven thousand, seven hundred twenty-nine".