1501561106661 has 64 divisors (see below), whose sum is σ = 2606312816640. Its totient is φ = 745634619840.

The previous prime is 1501561106659. The next prime is 1501561106687. The reversal of 1501561106661 is 1666011651051.

It is not a de Polignac number, because 1501561106661 - 2¹ = 1501561106659 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1501561106641) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 8192326 + ... + 8373608.

It is an arithmetic number, because the mean of its divisors is an integer number (40723637760).

Almost surely, 2^{1501561106661} is an apocalyptic number.

1501561106661 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1501561106661 is a deficient number, since it is larger than the sum of its proper divisors (1104751709979).

1501561106661 is a wasteful number, since it uses less digits than its factorization.

1501561106661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 182886.

The product of its (nonzero) digits is 32400, while the sum is 39.

The spelling of 1501561106661 in words is "one trillion, five hundred one billion, five hundred sixty-one million, one hundred six thousand, six hundred sixty-one".