142778338122121 has 9 divisors (see below), whose sum is σ = 154606297651029. Its totient is φ = 131795245647936.

The previous prime is 142778338122097. The next prime is 142778338122127. The reversal of 142778338122121 is 121221833877241.

It is a happy number.

The square root of 142778338122121 is 11948989.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 1294450032121 + 141483888090000 = 1137739^2 + 11894700^2 .

It is not a de Polignac number, because 142778338122121 - 2³³ = 142769748187529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (142778338122127) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 154877281 + ... + 155796433.

It is an arithmetic number, because the mean of its divisors is an integer number (17178477516781).

Almost surely, 2^{142778338122121} is an apocalyptic number.

142778338122121 is the 11948989-th square number.

142778338122121 is the 5974495-th centered octagonal number.

It is an amenable number.

142778338122121 is a deficient number, since it is larger than the sum of its proper divisors (11827959528908).

142778338122121 is an frugal number, since it uses more digits than its factorization.

142778338122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1838332 (or 919166 counting only the distinct ones).

The product of its digits is 1806336, while the sum is 52.

The spelling of 142778338122121 in words is "one hundred forty-two trillion, seven hundred seventy-eight billion, three hundred thirty-eight million, one hundred twenty-two thousand, one hundred twenty-one".