61281191287 has 4 divisors (see below), whose sum is σ = 61692474600. Its totient is φ = 60869907976.

The previous prime is 61281191239. The next prime is 61281191291. The reversal of 61281191287 is 78219118216.

61281191287 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 61281191287 - 2³¹ = 59133707639 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 (61281191227) 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, 205641433 + ... + 205641730.

It is an arithmetic number, because the mean of its divisors is an integer number (15423118650).

Almost surely, 2^61281191287 is an apocalyptic number.

61281191287 is a deficient number, since it is larger than the sum of its proper divisors (411283313).

61281191287 is a wasteful number, since it uses less digits than its factorization.

61281191287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 411283312.

The product of its digits is 96768, while the sum is 46.

The spelling of 61281191287 in words is "sixty-one billion, two hundred eighty-one million, one hundred ninety-one thousand, two hundred eighty-seven".