102815601605642 has 4 divisors (see below), whose sum is σ = 154223402408466. Its totient is φ = 51407800802820.

The previous prime is 102815601605641. The next prime is 102815601605657. The reversal of 102815601605642 is 246506106518201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 81265014413521 + 21550587192121 = 9014711^2 + 4642261^2 .

It is not an unprimeable number, because it can be changed into a prime (102815601605641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25703900401409 + ... + 25703900401412.

Almost surely, 2^{102815601605642} is an apocalyptic number.

102815601605642 is a deficient number, since it is larger than the sum of its proper divisors (51407800802824).

102815601605642 is an equidigital number, since it uses as much as digits as its factorization.

102815601605642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51407800802823.

The product of its (nonzero) digits is 691200, while the sum is 47.

The spelling of 102815601605642 in words is "one hundred two trillion, eight hundred fifteen billion, six hundred one million, six hundred five thousand, six hundred forty-two".