61865791 has 8 divisors (see below), whose sum is σ = 69521760. Its totient is φ = 54623712.

The previous prime is 61865743. The next prime is 61865827. The reversal of 61865791 is 19756816.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61865791 - 2¹⁹ = 61341503 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 (61865711) 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, 103156 + ... + 103753.

It is an arithmetic number, because the mean of its divisors is an integer number (8690220).

Almost surely, 2^61865791 is an apocalyptic number.

61865791 is a deficient number, since it is larger than the sum of its proper divisors (7655969).

61865791 is a wasteful number, since it uses less digits than its factorization.

61865791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 206945.

The product of its digits is 90720, while the sum is 43.

The square root of 61865791 is about 7865.4809770287. The cubic root of 61865791 is about 395.5033714976.

The spelling of 61865791 in words is "sixty-one million, eight hundred sixty-five thousand, seven hundred ninety-one".