661323050026 has 4 divisors (see below), whose sum is σ = 991984575042. Its totient is φ = 330661525012.

The previous prime is 661323050021. The next prime is 661323050057. The reversal of 661323050026 is 620050323166.

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., 645909579225 + 15413470801 = 803685^2 + 124151^2 .

It is a junction number, because it is equal to n+sod(n) for n = 661323049973 and 661323050000.

It is not an unprimeable number, because it can be changed into a prime (661323050021) 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, 165330762505 + ... + 165330762508.

Almost surely, 2^661323050026 is an apocalyptic number.

661323050026 is a deficient number, since it is larger than the sum of its proper divisors (330661525016).

661323050026 is a wasteful number, since it uses less digits than its factorization.

661323050026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330661525015.

The product of its (nonzero) digits is 38880, while the sum is 34.

The spelling of 661323050026 in words is "six hundred sixty-one billion, three hundred twenty-three million, fifty thousand, twenty-six".