66615280051 has 4 divisors (see below), whose sum is σ = 67553523504. Its totient is φ = 65677036600.

The previous prime is 66615280013. The next prime is 66615280063. The reversal of 66615280051 is 15008251666.

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 66615280051 - 2⁷ = 66615279923 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 66615279986 and 66615280013.

It is not an unprimeable number, because it can be changed into a prime (66615280091) 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, 469121620 + ... + 469121761.

It is an arithmetic number, because the mean of its divisors is an integer number (16888380876).

Almost surely, 2^66615280051 is an apocalyptic number.

66615280051 is a deficient number, since it is larger than the sum of its proper divisors (938243453).

66615280051 is an equidigital number, since it uses as much as digits as its factorization.

66615280051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 938243452.

The product of its (nonzero) digits is 86400, while the sum is 40.

The spelling of 66615280051 in words is "sixty-six billion, six hundred fifteen million, two hundred eighty thousand, fifty-one".