61620224 has 30 divisors (see below), whose sum is σ = 123269454. Its totient is φ = 30801920.

The previous prime is 61620199. The next prime is 61620227. The reversal of 61620224 is 42202616.

It can be written as a sum of positive squares in only one way, i.e., 51380224 + 10240000 = 7168^2 + 3200^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 61620224.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61620227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14504 + ... + 18264.

Almost surely, 2^61620224 is an apocalyptic number.

61620224 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 61620224, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61634727).

61620224 is an abundant number, since it is smaller than the sum of its proper divisors (61649230).

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

61620224 is an frugal number, since it uses more digits than its factorization.

61620224 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3789 (or 3763 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 23.

The square root of 61620224 is about 7849.8550305085. The cubic root of 61620224 is about 394.9793804330.

The spelling of 61620224 in words is "sixty-one million, six hundred twenty thousand, two hundred twenty-four".