661698345 has 64 divisors (see below), whose sum is σ = 1338716160. Its totient is φ = 271084800.

The previous prime is 661698329. The next prime is 661698397. The reversal of 661698345 is 543896166.

It is not a de Polignac number, because 661698345 - 2⁴ = 661698329 is a prime.

It is a super-3 number, since 3×661698345³ (a number of 27 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 661698294 and 661698303.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 77971 + ... + 86039.

It is an arithmetic number, because the mean of its divisors is an integer number (20917440).

Almost surely, 2^661698345 is an apocalyptic number.

It is an amenable number.

661698345 is an abundant number, since it is smaller than the sum of its proper divisors (677017815).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

661698345 is a wasteful number, since it uses less digits than its factorization.

661698345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8166.

The product of its digits is 933120, while the sum is 48.

The square root of 661698345 is about 25723.4979153303. The cubic root of 661698345 is about 871.4049370166.

The spelling of 661698345 in words is "six hundred sixty-one million, six hundred ninety-eight thousand, three hundred forty-five".