61253550 has 144 divisors (see below), whose sum is σ = 180442320. Its totient is φ = 15275520.

The previous prime is 61253513. The next prime is 61253557. The reversal of 61253550 is 5535216.

61253550 is a `hidden beast` number, since 61 + 2 + 53 + 550 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61253557) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 390072 + ... + 390228.

Almost surely, 2^61253550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61253550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (90221160).

61253550 is an abundant number, since it is smaller than the sum of its proper divisors (119188770).

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

61253550 is a wasteful number, since it uses less digits than its factorization.

61253550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 27.

The square root of 61253550 is about 7826.4647191436. The cubic root of 61253550 is about 394.1943735890.

Adding to 61253550 its reverse (5535216), we get a palindrome (66788766).

The spelling of 61253550 in words is "sixty-one million, two hundred fifty-three thousand, five hundred fifty".