1973611951609 has 27 divisors (see below), whose sum is σ = 2079017937423. Its totient is φ = 1873489483152.

The previous prime is 1973611951561. The next prime is 1973611951613. The reversal of 1973611951609 is 9061591163791.

The square root of 1973611951609 is 1404853.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1766015077225 + 207596874384 = 1328915^2 + 455628^2 .

It is not a de Polignac number, because 1973611951609 - 2⁷ = 1973611951481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1973611954609) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2235120682 + ... + 2235121564.

It is an arithmetic number, because the mean of its divisors is an integer number (77000664349).

Almost surely, 2^{1973611951609} is an apocalyptic number.

1973611951609 is the 1404853-rd square number.

1973611951609 is the 702427-th centered octagonal number.

It is an amenable number.

1973611951609 is a deficient number, since it is larger than the sum of its proper divisors (105405985814).

1973611951609 is an frugal number, since it uses more digits than its factorization.

1973611951609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1926 (or 963 counting only the distinct ones).

The product of its (nonzero) digits is 2755620, while the sum is 58.

The spelling of 1973611951609 in words is "one trillion, nine hundred seventy-three billion, six hundred eleven million, nine hundred fifty-one thousand, six hundred nine".