61521566 has 16 divisors (see below), whose sum is σ = 95739840. Its totient is φ = 29627520.

The previous prime is 61521541. The next prime is 61521569. The reversal of 61521566 is 66512516.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61521569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1730 + ... + 11226.

It is an arithmetic number, because the mean of its divisors is an integer number (5983740).

Almost surely, 2^61521566 is an apocalyptic number.

61521566 is a deficient number, since it is larger than the sum of its proper divisors (34218274).

61521566 is a wasteful number, since it uses less digits than its factorization.

61521566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9619.

The product of its digits is 10800, while the sum is 32.

The square root of 61521566 is about 7843.5684480981. The cubic root of 61521566 is about 394.7684719119.

The spelling of 61521566 in words is "sixty-one million, five hundred twenty-one thousand, five hundred sixty-six".