611720813 has 8 divisors (see below), whose sum is σ = 671020896. Its totient is φ = 553035600.

The previous prime is 611720803. The next prime is 611720821. The reversal of 611720813 is 318027116.

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 611720813 - 2²⁸ = 343285357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (611720803) 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, 151631 + ... + 155612.

It is an arithmetic number, because the mean of its divisors is an integer number (83877612).

Almost surely, 2^611720813 is an apocalyptic number.

It is an amenable number.

611720813 is a deficient number, since it is larger than the sum of its proper divisors (59300083).

611720813 is a wasteful number, since it uses less digits than its factorization.

611720813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307435.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 611720813 is about 24732.9903772269. The cubic root of 611720813 is about 848.8893512532.

Adding to 611720813 its reverse (318027116), we get a palindrome (929747929).

The spelling of 611720813 in words is "six hundred eleven million, seven hundred twenty thousand, eight hundred thirteen".