61644437 has 4 divisors (see below), whose sum is σ = 61985196. Its totient is φ = 61303680.

The previous prime is 61644421. The next prime is 61644449. The reversal of 61644437 is 73444616.

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

It can be written as a sum of positive squares in 2 ways, for example, as 398161 + 61246276 = 631^2 + 7826^2 .

It is a cyclic number.

It is not a de Polignac number, because 61644437 - 2⁴ = 61644421 is a prime.

It is a super-2 number, since 2×61644437² = 7600073226093938, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 61644397 and 61644406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61644487) 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, 170108 + ... + 170469.

It is an arithmetic number, because the mean of its divisors is an integer number (15496299).

Almost surely, 2^61644437 is an apocalyptic number.

It is an amenable number.

61644437 is a deficient number, since it is larger than the sum of its proper divisors (340759).

61644437 is a wasteful number, since it uses less digits than its factorization.

61644437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 340758.

The product of its digits is 48384, while the sum is 35.

The square root of 61644437 is about 7851.3971368158. The cubic root of 61644437 is about 395.0311079490.

It can be divided in two parts, 6164 and 4437, that added together give a palindrome (10601).

The spelling of 61644437 in words is "sixty-one million, six hundred forty-four thousand, four hundred thirty-seven".