642400453 has 4 divisors (see below), whose sum is σ = 643542048. Its totient is φ = 641258860.

The previous prime is 642400427. The next prime is 642400483. The reversal of 642400453 is 354004246.

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-642400453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642400483) 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, 569953 + ... + 571078.

It is an arithmetic number, because the mean of its divisors is an integer number (160885512).

Almost surely, 2^642400453 is an apocalyptic number.

It is an amenable number.

642400453 is a deficient number, since it is larger than the sum of its proper divisors (1141595).

642400453 is a wasteful number, since it uses less digits than its factorization.

642400453 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1141594.

The product of its (nonzero) digits is 11520, while the sum is 28.

The square root of 642400453 is about 25345.6199963623. The cubic root of 642400453 is about 862.8499524523.

Adding to 642400453 its reverse (354004246), we get a palindrome (996404699).

The spelling of 642400453 in words is "six hundred forty-two million, four hundred thousand, four hundred fifty-three".