61615220 has 24 divisors (see below), whose sum is σ = 131217408. Its totient is φ = 24298400.

The previous prime is 61615217. The next prime is 61615223. The reversal of 61615220 is 2251616.

61615220 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (61615217) and next prime (61615223).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61615223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20276 + ... + 23115.

It is an arithmetic number, because the mean of its divisors is an integer number (5467392).

Almost surely, 2^61615220 is an apocalyptic number.

It is an amenable number.

61615220 is an abundant number, since it is smaller than the sum of its proper divisors (69602188).

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

61615220 is a wasteful number, since it uses less digits than its factorization.

61615220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43471 (or 43469 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 61615220 is about 7849.5362920366. The cubic root of 61615220 is about 394.9686884329.

Adding to 61615220 its reverse (2251616), we get a palindrome (63866836).

The spelling of 61615220 in words is "sixty-one million, six hundred fifteen thousand, two hundred twenty".