61215615287 has 4 divisors (see below), whose sum is σ = 61293399576. Its totient is φ = 61137831000.

The previous prime is 61215615281. The next prime is 61215615289. The reversal of 61215615287 is 78251651216.

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 61215615287 - 2⁴ = 61215615271 is a prime.

It is a super-3 number, since 3×61215615287³ (a number of 33 digits) contains 333 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 (61215615281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38890964 + ... + 38892537.

It is an arithmetic number, because the mean of its divisors is an integer number (15323349894).

Almost surely, 2^61215615287 is an apocalyptic number.

61215615287 is a deficient number, since it is larger than the sum of its proper divisors (77784289).

61215615287 is an equidigital number, since it uses as much as digits as its factorization.

61215615287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77784288.

The product of its digits is 201600, while the sum is 44.

The spelling of 61215615287 in words is "sixty-one billion, two hundred fifteen million, six hundred fifteen thousand, two hundred eighty-seven".