661452246461 has 4 divisors (see below), whose sum is σ = 677585228124. Its totient is φ = 645319264800.

The previous prime is 661452246319. The next prime is 661452246479. The reversal of 661452246461 is 164642254166.

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 401219629561 + 260232616900 = 633419^2 + 510130^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-661452246461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661452246661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8066490770 + ... + 8066490851.

It is an arithmetic number, because the mean of its divisors is an integer number (169396307031).

Almost surely, 2^661452246461 is an apocalyptic number.

It is an amenable number.

661452246461 is a deficient number, since it is larger than the sum of its proper divisors (16132981663).

661452246461 is a wasteful number, since it uses less digits than its factorization.

661452246461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16132981662.

The product of its digits is 1658880, while the sum is 47.

The spelling of 661452246461 in words is "six hundred sixty-one billion, four hundred fifty-two million, two hundred forty-six thousand, four hundred sixty-one".