66157061 has 4 divisors (see below), whose sum is σ = 66273900. Its totient is φ = 66040224.

The previous prime is 66157057. The next prime is 66157079. The reversal of 66157061 is 16075166.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 38130625 + 28026436 = 6175^2 + 5294^2 .

It is a cyclic number.

It is not a de Polignac number, because 66157061 - 2² = 66157057 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66157051) 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, 57566 + ... + 58703.

It is an arithmetic number, because the mean of its divisors is an integer number (16568475).

Almost surely, 2^66157061 is an apocalyptic number.

It is an amenable number.

66157061 is a deficient number, since it is larger than the sum of its proper divisors (116839).

66157061 is a wasteful number, since it uses less digits than its factorization.

66157061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116838.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 66157061 is about 8133.6990969669. The cubic root of 66157061 is about 404.4443143748. Note that the first 3 decimals are identical.

The spelling of 66157061 in words is "sixty-six million, one hundred fifty-seven thousand, sixty-one".