61505601551 has 16 divisors (see below), whose sum is σ = 63336837984. Its totient is φ = 59702759424.

The previous prime is 61505601541. The next prime is 61505601607. The reversal of 61505601551 is 15510650516.

It is a cyclic number.

It is not a de Polignac number, because 61505601551 - 2³⁰ = 60431859727 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 (61505601541) 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, 5947181 + ... + 5957513.

It is an arithmetic number, because the mean of its divisors is an integer number (3958552374).

Almost surely, 2^61505601551 is an apocalyptic number.

61505601551 is a deficient number, since it is larger than the sum of its proper divisors (1831236433).

61505601551 is a wasteful number, since it uses less digits than its factorization.

61505601551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11690.

The product of its (nonzero) digits is 22500, while the sum is 35.

The spelling of 61505601551 in words is "sixty-one billion, five hundred five million, six hundred one thousand, five hundred fifty-one".