642505245 has 16 divisors (see below), whose sum is σ = 1037991552. Its totient is φ = 339341760.

The previous prime is 642505229. The next prime is 642505247. The reversal of 642505245 is 542505246.

It is not a de Polignac number, because 642505245 - 2⁴ = 642505229 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642505247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 206386 + ... + 209475.

It is an arithmetic number, because the mean of its divisors is an integer number (64874472).

Almost surely, 2^642505245 is an apocalyptic number.

It is an amenable number.

642505245 is a deficient number, since it is larger than the sum of its proper divisors (395486307).

642505245 is a wasteful number, since it uses less digits than its factorization.

642505245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 415972.

The product of its (nonzero) digits is 48000, while the sum is 33.

The square root of 642505245 is about 25347.6871726002. The cubic root of 642505245 is about 862.8968675584.

Subtracting from 642505245 its reverse (542505246), we obtain a palindrome (99999999).

The spelling of 642505245 in words is "six hundred forty-two million, five hundred five thousand, two hundred forty-five".