27561561501 has 16 divisors (see below), whose sum is σ = 37299132864. Its totient is φ = 18099817344.

The previous prime is 27561561451. The next prime is 27561561637. The reversal of 27561561501 is 10516516572.

It is a happy number.

It is not a de Polignac number, because 27561561501 - 2¹³ = 27561553309 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27561561501.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27561560501) 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, 95590 + ... + 253496.

It is an arithmetic number, because the mean of its divisors is an integer number (2331195804).

Almost surely, 2^27561561501 is an apocalyptic number.

It is an amenable number.

27561561501 is a deficient number, since it is larger than the sum of its proper divisors (9737571363).

27561561501 is a wasteful number, since it uses less digits than its factorization.

27561561501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158780.

The product of its (nonzero) digits is 63000, while the sum is 39.

The spelling of 27561561501 in words is "twenty-seven billion, five hundred sixty-one million, five hundred sixty-one thousand, five hundred one".