66780057 has 16 divisors (see below), whose sum is σ = 90538560. Its totient is φ = 43776192.

The previous prime is 66780047. The next prime is 66780059. The reversal of 66780057 is 75008766.

It is not a de Polignac number, because 66780057 - 2¹⁶ = 66714521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66779997 and 66780024.

It is not an unprimeable number, because it can be changed into a prime (66780059) 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 15 ways as a sum of consecutive naturals, for example, 66483 + ... + 67479.

It is an arithmetic number, because the mean of its divisors is an integer number (5658660).

Almost surely, 2^66780057 is an apocalyptic number.

It is an amenable number.

66780057 is a deficient number, since it is larger than the sum of its proper divisors (23758503).

66780057 is a wasteful number, since it uses less digits than its factorization.

66780057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1352.

The product of its (nonzero) digits is 70560, while the sum is 39.

The square root of 66780057 is about 8171.9065706847. The cubic root of 66780057 is about 405.7098904633.

The spelling of 66780057 in words is "sixty-six million, seven hundred eighty thousand, fifty-seven".