660451556431 has 4 divisors (see below), whose sum is σ = 660463173864. Its totient is φ = 660439939000.

The previous prime is 660451556423. The next prime is 660451556437. The reversal of 660451556431 is 134655154066.

It is a happy number.

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 660451556431 - 2³ = 660451556423 is a prime.

It is a super-2 number, since 2×660451556431² (a number of 24 digits) 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 (660451556437) 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, 5723020 + ... + 5837281.

It is an arithmetic number, because the mean of its divisors is an integer number (165115793466).

Almost surely, 2^660451556431 is an apocalyptic number.

660451556431 is a deficient number, since it is larger than the sum of its proper divisors (11617433).

660451556431 is a wasteful number, since it uses less digits than its factorization.

660451556431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11617432.

The product of its (nonzero) digits is 1296000, while the sum is 46.

The spelling of 660451556431 in words is "six hundred sixty billion, four hundred fifty-one million, five hundred fifty-six thousand, four hundred thirty-one".