661237773573 has 32 divisors (see below), whose sum is σ = 984359980800. Its totient is φ = 392023973376.

The previous prime is 661237773541. The next prime is 661237773593. The reversal of 661237773573 is 375377732166.

It is not a de Polignac number, because 661237773573 - 2⁵ = 661237773541 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661237773593) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 122793 + ... + 1156526.

It is an arithmetic number, because the mean of its divisors is an integer number (30761249400).

Almost surely, 2^661237773573 is an apocalyptic number.

It is an amenable number.

661237773573 is a deficient number, since it is larger than the sum of its proper divisors (323122207227).

661237773573 is a wasteful number, since it uses less digits than its factorization.

661237773573 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1279821.

The product of its digits is 23337720, while the sum is 57.

The spelling of 661237773573 in words is "six hundred sixty-one billion, two hundred thirty-seven million, seven hundred seventy-three thousand, five hundred seventy-three".