61555572 has 96 divisors (see below), whose sum is σ = 182044800. Its totient is φ = 17819136.

The previous prime is 61555547. The next prime is 61555577. The reversal of 61555572 is 27555516.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61555577) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22579 + ... + 25157.

It is an arithmetic number, because the mean of its divisors is an integer number (1896300).

Almost surely, 2^61555572 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61555572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (91022400).

61555572 is an abundant number, since it is smaller than the sum of its proper divisors (120489228).

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

61555572 is a wasteful number, since it uses less digits than its factorization.

61555572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2622 (or 2614 counting only the distinct ones).

The product of its digits is 52500, while the sum is 36.

The square root of 61555572 is about 7845.7359119461. The cubic root of 61555572 is about 394.8411945079.

The spelling of 61555572 in words is "sixty-one million, five hundred fifty-five thousand, five hundred seventy-two".