661012423 has 8 divisors (see below), whose sum is σ = 665745408. Its totient is φ = 656295864.

The previous prime is 661012403. The next prime is 661012427. The reversal of 661012423 is 324210166.

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 661012423 - 2²⁵ = 627457991 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 (661012427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 83140 + ... + 90742.

It is an arithmetic number, because the mean of its divisors is an integer number (83218176).

Almost surely, 2^661012423 is an apocalyptic number.

661012423 is a deficient number, since it is larger than the sum of its proper divisors (4732985).

661012423 is a wasteful number, since it uses less digits than its factorization.

661012423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8213.

The product of its (nonzero) digits is 1728, while the sum is 25.

The square root of 661012423 is about 25710.1618625788. The cubic root of 661012423 is about 871.1037310501.

Adding to 661012423 its reverse (324210166), we get a palindrome (985222589).

The spelling of 661012423 in words is "six hundred sixty-one million, twelve thousand, four hundred twenty-three".