51660601566 has 32 divisors (see below), whose sum is σ = 122153149440. Its totient is φ = 14251200096.

The previous prime is 51660601561. The next prime is 51660601583. The reversal of 51660601566 is 66510606615.

51660601566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×51660601566² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51660601561) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21205926 + ... + 21208361.

It is an arithmetic number, because the mean of its divisors is an integer number (3817285920).

Almost surely, 2^51660601566 is an apocalyptic number.

51660601566 is an abundant number, since it is smaller than the sum of its proper divisors (70492547874).

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

51660601566 is a wasteful number, since it uses less digits than its factorization.

51660601566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42414328.

The product of its (nonzero) digits is 194400, while the sum is 42.

The spelling of 51660601566 in words is "fifty-one billion, six hundred sixty million, six hundred one thousand, five hundred sixty-six".