66137540 has 24 divisors (see below), whose sum is σ = 158730432. Its totient is φ = 22675680.

The previous prime is 66137501. The next prime is 66137543. The reversal of 66137540 is 4573166.

It is a junction number, because it is equal to n+sod(n) for n = 66137497 and 66137506.

It is not an unprimeable number, because it can be changed into a prime (66137543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236066 + ... + 236345.

It is an arithmetic number, because the mean of its divisors is an integer number (6613768).

Almost surely, 2^66137540 is an apocalyptic number.

It is an amenable number.

66137540 is an abundant number, since it is smaller than the sum of its proper divisors (92592892).

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

66137540 is a wasteful number, since it uses less digits than its factorization.

66137540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 472427 (or 472425 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 66137540 is about 8132.4990009222. The cubic root of 66137540 is about 404.4045305935.

The spelling of 66137540 in words is "sixty-six million, one hundred thirty-seven thousand, five hundred forty".