641890 has 8 divisors (see below), whose sum is σ = 1155420. Its totient is φ = 256752.

The previous prime is 641881. The next prime is 641891. The reversal of 641890 is 98146.

641890 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 641601 + 289 = 801^2 + 17^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (641891) 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, 32085 + ... + 32104.

2⁶⁴¹⁸⁹⁰ is an apocalyptic number.

641890 is a deficient number, since it is larger than the sum of its proper divisors (513530).

641890 is a wasteful number, since it uses less digits than its factorization.

641890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64196.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 641890 is about 801.1803791906. The cubic root of 641890 is about 86.2621350985.

The spelling of 641890 in words is "six hundred forty-one thousand, eight hundred ninety".