721682677 has 4 divisors (see below), whose sum is σ = 722749356. Its totient is φ = 720616000.

The previous prime is 721682659. The next prime is 721682699. The reversal of 721682677 is 776286127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 776286127 = 23321 ⋅33287.

It can be written as a sum of positive squares in 2 ways, for example, as 703628676 + 18054001 = 26526^2 + 4249^2 .

It is a cyclic number.

It is not a de Polignac number, because 721682677 - 2²³ = 713294069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721682627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532324 + ... + 533677.

It is an arithmetic number, because the mean of its divisors is an integer number (180687339).

Almost surely, 2^721682677 is an apocalyptic number.

It is an amenable number.

721682677 is a deficient number, since it is larger than the sum of its proper divisors (1066679).

721682677 is a wasteful number, since it uses less digits than its factorization.

721682677 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1066678.

The product of its digits is 395136, while the sum is 46.

The square root of 721682677 is about 26864.1522665429. The cubic root of 721682677 is about 896.9786243051.

The spelling of 721682677 in words is "seven hundred twenty-one million, six hundred eighty-two thousand, six hundred seventy-seven".