661693063 has 4 divisors (see below), whose sum is σ = 661798648. Its totient is φ = 661587480.

The previous prime is 661693061. The next prime is 661693079. The reversal of 661693063 is 360396166.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 661693063 - 2¹ = 661693061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661693061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42756 + ... + 56137.

It is an arithmetic number, because the mean of its divisors is an integer number (165449662).

Almost surely, 2^661693063 is an apocalyptic number.

661693063 is a deficient number, since it is larger than the sum of its proper divisors (105585).

661693063 is an equidigital number, since it uses as much as digits as its factorization.

661693063 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105584.

The product of its (nonzero) digits is 104976, while the sum is 40.

The square root of 661693063 is about 25723.3952463511. The cubic root of 661693063 is about 871.4026183502.

The spelling of 661693063 in words is "six hundred sixty-one million, six hundred ninety-three thousand, sixty-three".