642492 has 36 divisors (see below), whose sum is σ = 1686776. Its totient is φ = 213840.

The previous prime is 642487. The next prime is 642517. The reversal of 642492 is 294246.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 642492.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 642 + ... + 1302.

2⁶⁴²⁴⁹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 642492, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (843388).

642492 is an abundant number, since it is smaller than the sum of its proper divisors (1044284).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

642492 is a wasteful number, since it uses less digits than its factorization.

642492 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 666 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 642492 is about 801.5559868156. Note that the first 3 decimals coincide. The cubic root of 642492 is about 86.2890938088.

It can be divided in two parts, 64 and 2492, that added together give a triangular number (2556 = T₇₁).

The spelling of 642492 in words is "six hundred forty-two thousand, four hundred ninety-two".