61665655015715 has 4 divisors (see below), whose sum is σ = 73998786018864. Its totient is φ = 49332524012568.

The previous prime is 61665655015709. The next prime is 61665655015739. The reversal of 61665655015715 is 51751055656616.

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 61665655015715 - 2³⁶ = 61596935538979 is a prime.

It is a super-2 number, since 2×61665655015715² (a number of 28 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6166565501567 + ... + 6166565501576.

It is an arithmetic number, because the mean of its divisors is an integer number (18499696504716).

Almost surely, 2^{61665655015715} is an apocalyptic number.

61665655015715 is a deficient number, since it is larger than the sum of its proper divisors (12333131003149).

61665655015715 is a wasteful number, since it uses less digits than its factorization.

61665655015715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12333131003148.

The product of its (nonzero) digits is 28350000, while the sum is 59.

The spelling of 61665655015715 in words is "sixty-one trillion, six hundred sixty-five billion, six hundred fifty-five million, fifteen thousand, seven hundred fifteen".