61415220 has 96 divisors (see below), whose sum is σ = 191721600. Its totient is φ = 14598144.

The previous prime is 61415219. The next prime is 61415273. The reversal of 61415220 is 2251416.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17796 + ... + 20964.

It is an arithmetic number, because the mean of its divisors is an integer number (1997100).

Almost surely, 2^61415220 is an apocalyptic number.

61415220 is a gapful number since it is divisible by the number (60) 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 61415220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95860800).

61415220 is an abundant number, since it is smaller than the sum of its proper divisors (130306380).

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

61415220 is a wasteful number, since it uses less digits than its factorization.

61415220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217 (or 3215 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 21.

The square root of 61415220 is about 7836.7863311437. The cubic root of 61415220 is about 394.5408755100.

Adding to 61415220 its reverse (2251416), we get a palindrome (63666636).

The spelling of 61415220 in words is "sixty-one million, four hundred fifteen thousand, two hundred twenty".