642444645 has 16 divisors (see below), whose sum is σ = 1049783040. Its totient is φ = 335346624.

The previous prime is 642444643. The next prime is 642444679. The reversal of 642444645 is 546444246.

It is not a de Polignac number, because 642444645 - 2¹ = 642444643 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642444643) 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, 454930 + ... + 456339.

It is an arithmetic number, because the mean of its divisors is an integer number (65611440).

Almost surely, 2^642444645 is an apocalyptic number.

It is an amenable number.

642444645 is a deficient number, since it is larger than the sum of its proper divisors (407338395).

642444645 is a wasteful number, since it uses less digits than its factorization.

642444645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911324.

The product of its digits is 368640, while the sum is 39.

The square root of 642444645 is about 25346.4917690792. The cubic root of 642444645 is about 862.8697377179.

The spelling of 642444645 in words is "six hundred forty-two million, four hundred forty-four thousand, six hundred forty-five".