61097791 has 4 divisors (see below), whose sum is σ = 62397792. Its totient is φ = 59797792.

The previous prime is 61097723. The next prime is 61097873. The reversal of 61097791 is 19779016.

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 61097791 - 2⁹ = 61097279 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 (61097291) 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, 649930 + ... + 650023.

It is an arithmetic number, because the mean of its divisors is an integer number (15599448).

Almost surely, 2^61097791 is an apocalyptic number.

61097791 is a deficient number, since it is larger than the sum of its proper divisors (1300001).

61097791 is a wasteful number, since it uses less digits than its factorization.

61097791 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1300000.

The product of its (nonzero) digits is 23814, while the sum is 40.

The square root of 61097791 is about 7816.5075961071. The cubic root of 61097791 is about 393.8599633750.

The spelling of 61097791 in words is "sixty-one million, ninety-seven thousand, seven hundred ninety-one".