61515516161 has 16 divisors (see below), whose sum is σ = 67657033728. Its totient is φ = 55465804800.

The previous prime is 61515516133. The next prime is 61515516169. The reversal of 61515516161 is 16161551516.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 61515516161 - 2¹⁰ = 61515515137 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61515516169) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7597031 + ... + 7605123.

It is an arithmetic number, because the mean of its divisors is an integer number (4228564608).

Almost surely, 2^61515516161 is an apocalyptic number.

It is an amenable number.

61515516161 is a deficient number, since it is larger than the sum of its proper divisors (6141517567).

61515516161 is a wasteful number, since it uses less digits than its factorization.

61515516161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13672.

The product of its digits is 27000, while the sum is 38.

The spelling of 61515516161 in words is "sixty-one billion, five hundred fifteen million, five hundred sixteen thousand, one hundred sixty-one".