661211510065113 has 32 divisors (see below), whose sum is σ = 1042306182835200. Its totient is φ = 364805536769856.

The previous prime is 661211510065111. The next prime is 661211510065187. The reversal of 661211510065113 is 311560015112166.

It is not a de Polignac number, because 661211510065113 - 2¹ = 661211510065111 is a prime.

It is a super-2 number, since 2×661211510065113² (a number of 30 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (661211510065111) 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, 360941370 + ... + 362768652.

It is an arithmetic number, because the mean of its divisors is an integer number (32572068213600).

Almost surely, 2^{661211510065113} is an apocalyptic number.

It is an amenable number.

661211510065113 is a deficient number, since it is larger than the sum of its proper divisors (381094672770087).

661211510065113 is a wasteful number, since it uses less digits than its factorization.

661211510065113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2421501.

The product of its (nonzero) digits is 32400, while the sum is 39.

Adding to 661211510065113 its reverse (311560015112166), we get a palindrome (972771525177279).

The spelling of 661211510065113 in words is "six hundred sixty-one trillion, two hundred eleven billion, five hundred ten million, sixty-five thousand, one hundred thirteen".