512103400305661 has 4 divisors (see below), whose sum is σ = 512374497925500. Its totient is φ = 511832302685824.

The previous prime is 512103400305593. The next prime is 512103400305689. The reversal of 512103400305661 is 166503004301215.

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

It can be written as a sum of positive squares in 2 ways, for example, as 116450126934436 + 395653273371225 = 10791206^2 + 19891035^2 .

It is a cyclic number.

It is not a de Polignac number, because 512103400305661 - 2⁷ = 512103400305533 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 512103400305661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (512103700305661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 135548807086 + ... + 135548810863.

It is an arithmetic number, because the mean of its divisors is an integer number (128093624481375).

Almost surely, 2^{512103400305661} is an apocalyptic number.

It is an amenable number.

512103400305661 is a deficient number, since it is larger than the sum of its proper divisors (271097619839).

512103400305661 is a wasteful number, since it uses less digits than its factorization.

512103400305661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271097619838.

The product of its (nonzero) digits is 64800, while the sum is 37.

Adding to 512103400305661 its reverse (166503004301215), we get a palindrome (678606404606876).

The spelling of 512103400305661 in words is "five hundred twelve trillion, one hundred three billion, four hundred million, three hundred five thousand, six hundred sixty-one".