642461 has 4 divisors (see below), whose sum is σ = 648924. Its totient is φ = 636000.

The previous prime is 642457. The next prime is 642487. The reversal of 642461 is 164246.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 422500 + 219961 = 650^2 + 469^2 .

It is a cyclic number.

It is not a de Polignac number, because 642461 - 2² = 642457 is a prime.

It is a super-2 number, since 2×642461² = 825512273042, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642361) 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, 3080 + ... + 3281.

It is an arithmetic number, because the mean of its divisors is an integer number (162231).

2⁶⁴²⁴⁶¹ is an apocalyptic number.

It is an amenable number.

642461 is a deficient number, since it is larger than the sum of its proper divisors (6463).

642461 is a wasteful number, since it uses less digits than its factorization.

642461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6462.

The product of its digits is 1152, while the sum is 23.

The square root of 642461 is about 801.5366491933. The cubic root of 642461 is about 86.2877059809.

The spelling of 642461 in words is "six hundred forty-two thousand, four hundred sixty-one".