642940006145 has 4 divisors (see below), whose sum is σ = 771528007380. Its totient is φ = 514352004912.

The previous prime is 642940006127. The next prime is 642940006201. The reversal of 642940006145 is 541600049246.

642940006145 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 541600049246 = 2 ⋅270800024623.

It can be written as a sum of positive squares in 2 ways, for example, as 128955682816 + 513984323329 = 359104^2 + 716927^2 .

It is a cyclic number.

It is not a de Polignac number, because 642940006145 - 2⁸ = 642940005889 is a prime.

It is a super-2 number, since 2×642940006145² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64294000610 + ... + 64294000619.

It is an arithmetic number, because the mean of its divisors is an integer number (192882001845).

Almost surely, 2^642940006145 is an apocalyptic number.

It is an amenable number.

642940006145 is a deficient number, since it is larger than the sum of its proper divisors (128588001235).

642940006145 is a wasteful number, since it uses less digits than its factorization.

642940006145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128588001234.

The product of its (nonzero) digits is 207360, while the sum is 41.

The spelling of 642940006145 in words is "six hundred forty-two billion, nine hundred forty million, six thousand, one hundred forty-five".