66061491 has 4 divisors (see below), whose sum is σ = 88081992. Its totient is φ = 44040992.

The previous prime is 66061483. The next prime is 66061493. The reversal of 66061491 is 19416066.

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 66061491 - 2³ = 66061483 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66061493) 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, 11010246 + ... + 11010251.

It is an arithmetic number, because the mean of its divisors is an integer number (22020498).

Almost surely, 2^66061491 is an apocalyptic number.

66061491 is a deficient number, since it is larger than the sum of its proper divisors (22020501).

66061491 is a wasteful number, since it uses less digits than its factorization.

66061491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22020500.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 66061491 is about 8127.8220329926. The cubic root of 66061491 is about 404.2494681005.

The spelling of 66061491 in words is "sixty-six million, sixty-one thousand, four hundred ninety-one".