1720661260105 has 32 divisors (see below), whose sum is σ = 2159554118400.
Its totient is φ = 1313635276800.
The previous prime is 1720661260103. The next prime is 1720661260117. The reversal of 1720661260105 is 5010621660271.
It is a happy number.
It is not a de Polignac number, because 1720661260105 - 21 = 1720661260103 is a prime.
It is a super-2 number, since 2×17206612601052 (a number of 25 digits) contains 22 as substring.
It is not an unprimeable number, because it can be changed into a prime (1720661260103) 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, 119077921 + ... + 119092369.
It is an arithmetic number, because the mean of its divisors is an integer number (67486066200).
Almost surely, 21720661260105 is an apocalyptic number.
It is an amenable number.
1720661260105 is a deficient number, since it is larger than the sum of its proper divisors (438892858295).
1720661260105 is a wasteful number, since it uses less digits than its factorization.
1720661260105 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 16801.
The product of its (nonzero) digits is 30240, while the sum is 37.
The spelling of 1720661260105 in words is "one trillion, seven hundred twenty billion, six hundred sixty-one million, two hundred sixty thousand, one hundred five".