10661220645515 has 16 divisors (see below), whose sum is σ = 13973342438880. Its totient is φ = 7744262008320.

The previous prime is 10661220645511. The next prime is 10661220645521. The reversal of 10661220645515 is 51554602216601.

It is not a de Polignac number, because 10661220645515 - 2² = 10661220645511 is a prime.

It is a super-2 number, since 2×10661220645515² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (10661220645511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116866574 + ... + 116957763.

It is an arithmetic number, because the mean of its divisors is an integer number (873333902430).

Almost surely, 2^{10661220645515} is an apocalyptic number.

10661220645515 is a deficient number, since it is larger than the sum of its proper divisors (3312121793365).

10661220645515 is a wasteful number, since it uses less digits than its factorization.

10661220645515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233825182.

The product of its (nonzero) digits is 432000, while the sum is 44.

The spelling of 10661220645515 in words is "ten trillion, six hundred sixty-one billion, two hundred twenty million, six hundred forty-five thousand, five hundred fifteen".