61528791 has 4 divisors (see below), whose sum is σ = 82038392. Its totient is φ = 41019192.

The previous prime is 61528777. The next prime is 61528811. The reversal of 61528791 is 19782516.

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

It is not a de Polignac number, because 61528791 - 2⁵ = 61528759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61528711) 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 3 ways as a sum of consecutive naturals, for example, 10254796 + ... + 10254801.

It is an arithmetic number, because the mean of its divisors is an integer number (20509598).

Almost surely, 2^61528791 is an apocalyptic number.

61528791 is a deficient number, since it is larger than the sum of its proper divisors (20509601).

61528791 is a wasteful number, since it uses less digits than its factorization.

61528791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20509600.

The product of its digits is 30240, while the sum is 39.

The square root of 61528791 is about 7844.0290030060. The cubic root of 61528791 is about 394.7839249785.

The spelling of 61528791 in words is "sixty-one million, five hundred twenty-eight thousand, seven hundred ninety-one".