61813439 has 4 divisors (see below), whose sum is σ = 62258280. Its totient is φ = 61368600.

The previous prime is 61813429. The next prime is 61813447. The reversal of 61813439 is 93431816.

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 61813439 - 2⁸ = 61813183 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61813399 and 61813408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61813429) 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, 222212 + ... + 222489.

It is an arithmetic number, because the mean of its divisors is an integer number (15564570).

Almost surely, 2^61813439 is an apocalyptic number.

61813439 is a deficient number, since it is larger than the sum of its proper divisors (444841).

61813439 is a wasteful number, since it uses less digits than its factorization.

61813439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444840.

The product of its digits is 15552, while the sum is 35.

The square root of 61813439 is about 7862.1523134572. The cubic root of 61813439 is about 395.3917792087.

The spelling of 61813439 in words is "sixty-one million, eight hundred thirteen thousand, four hundred thirty-nine".