693721 has 4 divisors (see below), whose sum is σ = 792832. Its totient is φ = 594612.

The previous prime is 693701. The next prime is 693727. The reversal of 693721 is 127396.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 693721 - 2⁵ = 693689 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 693721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (693727) 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, 49545 + ... + 49558.

It is an arithmetic number, because the mean of its divisors is an integer number (198208).

2⁶⁹³⁷²¹ is an apocalyptic number.

It is an amenable number.

693721 is a deficient number, since it is larger than the sum of its proper divisors (99111).

693721 is an equidigital number, since it uses as much as digits as its factorization.

693721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99110.

The product of its digits is 2268, while the sum is 28.

The square root of 693721 is about 832.8991535594. The cubic root of 693721 is about 88.5241191031.

The spelling of 693721 in words is "six hundred ninety-three thousand, seven hundred twenty-one".