66156201 has 18 divisors (see below), whose sum is σ = 98753850. Its totient is φ = 42675840.

The previous prime is 66156191. The next prime is 66156227. The reversal of 66156201 is 10265166.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 39992976 + 26163225 = 6324^2 + 5115^2 .

It is not a de Polignac number, because 66156201 - 2¹³ = 66148009 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66152201) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4825 + ... + 12473.

It is an arithmetic number, because the mean of its divisors is an integer number (5486325).

Almost surely, 2^66156201 is an apocalyptic number.

It is an amenable number.

66156201 is a deficient number, since it is larger than the sum of its proper divisors (32597649).

66156201 is a wasteful number, since it uses less digits than its factorization.

66156201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7717 (or 7683 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 66156201 is about 8133.6462303201. The cubic root of 66156201 is about 404.4425618603.

The spelling of 66156201 in words is "sixty-six million, one hundred fifty-six thousand, two hundred one".