661710919 has 2 divisors, whose sum is σ = 661710920. Its totient is φ = 661710918.

The previous prime is 661710899. The next prime is 661710949. The reversal of 661710919 is 919017166.

661710919 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 661710919 - 2⁵ = 661710887 is a prime.

It is a super-2 number, since 2×661710919² = 875722680647649122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (661710949) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 330855459 + 330855460.

It is an arithmetic number, because the mean of its divisors is an integer number (330855460).

Almost surely, 2^661710919 is an apocalyptic number.

661710919 is a deficient number, since it is larger than the sum of its proper divisors (1).

661710919 is an equidigital number, since it uses as much as digits as its factorization.

661710919 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20412, while the sum is 40.

The square root of 661710919 is about 25723.7423210543. The cubic root of 661710919 is about 871.4104566396.

The spelling of 661710919 in words is "six hundred sixty-one million, seven hundred ten thousand, nine hundred nineteen".