61647715391 has 8 divisors (see below), whose sum is σ = 61700106000. Its totient is φ = 61595352000.

The previous prime is 61647715369. The next prime is 61647715399. The reversal of 61647715391 is 19351774616.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 61647715391 - 2¹⁸ = 61647453247 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 (61647715399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7645520 + ... + 7653578.

It is an arithmetic number, because the mean of its divisors is an integer number (7712513250).

Almost surely, 2^61647715391 is an apocalyptic number.

61647715391 is a deficient number, since it is larger than the sum of its proper divisors (52390609).

61647715391 is a wasteful number, since it uses less digits than its factorization.

61647715391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13609.

The product of its digits is 952560, while the sum is 50.

The spelling of 61647715391 in words is "sixty-one billion, six hundred forty-seven million, seven hundred fifteen thousand, three hundred ninety-one".