617680781 has 8 divisors (see below), whose sum is σ = 621784800. Its totient is φ = 613584720.

The previous prime is 617680741. The next prime is 617680783. The reversal of 617680781 is 187086716.

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

It is a cyclic number.

It is not a de Polignac number, because 617680781 - 2⁶ = 617680717 is a prime.

It is a super-2 number, since 2×617680781² = 763059094433539922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (617680783) 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, 262910 + ... + 265248.

It is an arithmetic number, because the mean of its divisors is an integer number (77723100).

Almost surely, 2^617680781 is an apocalyptic number.

It is an amenable number.

617680781 is a deficient number, since it is larger than the sum of its proper divisors (4104019).

617680781 is a wasteful number, since it uses less digits than its factorization.

617680781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3979.

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 617680781 is about 24853.1845243220. The cubic root of 617680781 is about 851.6373427165.

The spelling of 617680781 in words is "six hundred seventeen million, six hundred eighty thousand, seven hundred eighty-one".