661894327 has 4 divisors (see below), whose sum is σ = 662140480. Its totient is φ = 661648176.

The previous prime is 661894319. The next prime is 661894339. The reversal of 661894327 is 723498166.

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 661894327 - 2³ = 661894319 is a prime.

It is a super-2 number, since 2×661894327² = 876208200229565858, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (661894307) 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 3 ways as a sum of consecutive naturals, for example, 118998 + ... + 124435.

It is an arithmetic number, because the mean of its divisors is an integer number (165535120).

Almost surely, 2^661894327 is an apocalyptic number.

661894327 is a deficient number, since it is larger than the sum of its proper divisors (246153).

661894327 is a wasteful number, since it uses less digits than its factorization.

661894327 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 246152.

The product of its digits is 435456, while the sum is 46.

The square root of 661894327 is about 25727.3070296912. The cubic root of 661894327 is about 871.4909595100.

The spelling of 661894327 in words is "six hundred sixty-one million, eight hundred ninety-four thousand, three hundred twenty-seven".