61555545271 has 4 divisors (see below), whose sum is σ = 67151503944. Its totient is φ = 55959586600.

The previous prime is 61555545269. The next prime is 61555545353. The reversal of 61555545271 is 17254555516.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61555545271 - 2¹ = 61555545269 is a prime.

It is a super-2 number, since 2×61555545271² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61555540271) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2797979320 + ... + 2797979341.

It is an arithmetic number, because the mean of its divisors is an integer number (16787875986).

Almost surely, 2^61555545271 is an apocalyptic number.

61555545271 is a deficient number, since it is larger than the sum of its proper divisors (5595958673).

61555545271 is a wasteful number, since it uses less digits than its factorization.

61555545271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5595958672.

The product of its digits is 1050000, while the sum is 46.

The spelling of 61555545271 in words is "sixty-one billion, five hundred fifty-five million, five hundred forty-five thousand, two hundred seventy-one".