642757451 has 24 divisors (see below), whose sum is σ = 786725856. Its totient is φ = 522910080.

The previous prime is 642757397. The next prime is 642757457. The reversal of 642757451 is 154757246.

It is not a de Polignac number, because 642757451 - 2¹⁴ = 642741067 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a junction number, because it is equal to n+sod(n) for n = 642757399 and 642757408.

It is not an unprimeable number, because it can be changed into a prime (642757457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 70010 + ... + 78656.

It is an arithmetic number, because the mean of its divisors is an integer number (32780244).

Almost surely, 2^642757451 is an apocalyptic number.

642757451 is a deficient number, since it is larger than the sum of its proper divisors (143968405).

642757451 is a wasteful number, since it uses less digits than its factorization.

642757451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8739 (or 8732 counting only the distinct ones).

The product of its digits is 235200, while the sum is 41.

The square root of 642757451 is about 25352.6616156963. The cubic root of 642757451 is about 863.0097586202.

The spelling of 642757451 in words is "six hundred forty-two million, seven hundred fifty-seven thousand, four hundred fifty-one".