690641 has 4 divisors (see below), whose sum is σ = 789312. Its totient is φ = 591972.

The previous prime is 690629. The next prime is 690661. The reversal of 690641 is 146096.

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 a de Polignac number, because none of the positive numbers 2^k-690641 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 690641.

It is not an unprimeable number, because it can be changed into a prime (690611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49325 + ... + 49338.

It is an arithmetic number, because the mean of its divisors is an integer number (197328).

2⁶⁹⁰⁶⁴¹ is an apocalyptic number.

It is an amenable number.

690641 is a deficient number, since it is larger than the sum of its proper divisors (98671).

690641 is an equidigital number, since it uses as much as digits as its factorization.

690641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 98670.

The product of its (nonzero) digits is 1296, while the sum is 26.

The square root of 690641 is about 831.0481333834. The cubic root of 690641 is about 88.3929141963.

It can be divided in two parts, 690 and 641, that added together give a palindrome (1331).

The spelling of 690641 in words is "six hundred ninety thousand, six hundred forty-one".