61399744 has 56 divisors (see below), whose sum is σ = 142138400. Its totient is φ = 26304768.

The previous prime is 61399727. The next prime is 61399799. The reversal of 61399744 is 44799316.

It is a tau number, because it is divible by the number of its divisors (56).

It is a self number, because there is not a number n which added to its sum of digits gives 61399744.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20554 + ... + 23350.

Almost surely, 2^61399744 is an apocalyptic number.

61399744 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61399744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (71069200).

61399744 is an abundant number, since it is smaller than the sum of its proper divisors (80738656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61399744 is an equidigital number, since it uses as much as digits as its factorization.

61399744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2830 (or 2806 counting only the distinct ones).

The product of its digits is 163296, while the sum is 43.

The square root of 61399744 is about 7835.7988743969. The cubic root of 61399744 is about 394.5077326532.

The spelling of 61399744 in words is "sixty-one million, three hundred ninety-nine thousand, seven hundred forty-four".