1661522780023 has 8 divisors (see below), whose sum is σ = 1816009718400. Its totient is φ = 1513341431040.

The previous prime is 1661522779981. The next prime is 1661522780063. The reversal of 1661522780023 is 3200872251661.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1661522780023 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 (1661522780063) 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, 1576396798 + ... + 1576397851.

It is an arithmetic number, because the mean of its divisors is an integer number (227001214800).

Almost surely, 2^{1661522780023} is an apocalyptic number.

1661522780023 is a deficient number, since it is larger than the sum of its proper divisors (154486938377).

1661522780023 is a wasteful number, since it uses less digits than its factorization.

1661522780023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3152794697.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 1661522780023 in words is "one trillion, six hundred sixty-one billion, five hundred twenty-two million, seven hundred eighty thousand, twenty-three".