61504399 has 4 divisors (see below), whose sum is σ = 67095720. Its totient is φ = 55913080.

The previous prime is 61504393. The next prime is 61504427. The reversal of 61504399 is 99340516.

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 61504399 - 2⁷ = 61504271 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 (61504393) 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, 2795644 + ... + 2795665.

It is an arithmetic number, because the mean of its divisors is an integer number (16773930).

Almost surely, 2^61504399 is an apocalyptic number.

61504399 is a deficient number, since it is larger than the sum of its proper divisors (5591321).

61504399 is a wasteful number, since it uses less digits than its factorization.

61504399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5591320.

The product of its (nonzero) digits is 29160, while the sum is 37.

The square root of 61504399 is about 7842.4740356599. The cubic root of 61504399 is about 394.7317497171.

The spelling of 61504399 in words is "sixty-one million, five hundred four thousand, three hundred ninety-nine".