61100520 has 128 divisors (see below), whose sum is σ = 201398400. Its totient is φ = 14736384.

The previous prime is 61100509. The next prime is 61100539. The reversal of 61100520 is 2500116.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 61100520.

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, 82311 + ... + 83049.

It is an arithmetic number, because the mean of its divisors is an integer number (1573425).

Almost surely, 2^61100520 is an apocalyptic number.

61100520 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 61100520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100699200).

61100520 is an abundant number, since it is smaller than the sum of its proper divisors (140297880).

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

61100520 is a wasteful number, since it uses less digits than its factorization.

61100520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 819 (or 815 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 15.

The square root of 61100520 is about 7816.6821606101. The cubic root of 61100520 is about 393.8658273504.

Adding to 61100520 its reverse (2500116), we get a palindrome (63600636).

The spelling of 61100520 in words is "sixty-one million, one hundred thousand, five hundred twenty".