661264034143 has 4 divisors (see below), whose sum is σ = 661414428360. Its totient is φ = 661113639928.

The previous prime is 661264034131. The next prime is 661264034149. The reversal of 661264034143 is 341430462166.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 341430462166 = 2 ⋅170715231083.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661264034143 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 661264034096 and 661264034105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661264034149) 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 in 3 ways as a sum of consecutive naturals, for example, 75190513 + ... + 75199306.

It is an arithmetic number, because the mean of its divisors is an integer number (165353607090).

Almost surely, 2^661264034143 is an apocalyptic number.

661264034143 is a deficient number, since it is larger than the sum of its proper divisors (150394217).

661264034143 is a wasteful number, since it uses less digits than its factorization.

661264034143 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150394216.

The product of its (nonzero) digits is 248832, while the sum is 40.

The spelling of 661264034143 in words is "six hundred sixty-one billion, two hundred sixty-four million, thirty-four thousand, one hundred forty-three".