661361512245 has 32 divisors (see below), whose sum is σ = 1209395336448. Its totient is φ = 302324548608.

The previous prime is 661361512243. The next prime is 661361512271. The reversal of 661361512245 is 542215163166.

It is not a de Polignac number, because 661361512245 - 2¹ = 661361512243 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 661361512197 and 661361512206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661361512241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2827197 + ... + 3052173.

It is an arithmetic number, because the mean of its divisors is an integer number (37793604264).

Almost surely, 2^661361512245 is an apocalyptic number.

It is an amenable number.

661361512245 is a deficient number, since it is larger than the sum of its proper divisors (548033824203).

661361512245 is a wasteful number, since it uses less digits than its factorization.

661361512245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252989.

The product of its digits is 259200, while the sum is 42.

The spelling of 661361512245 in words is "six hundred sixty-one billion, three hundred sixty-one million, five hundred twelve thousand, two hundred forty-five".