61333640 has 64 divisors (see below), whose sum is σ = 145238400. Its totient is φ = 23265792.

The previous prime is 61333621. The next prime is 61333669. The reversal of 61333640 is 4633316.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 149756 + ... + 150164.

It is an arithmetic number, because the mean of its divisors is an integer number (2269350).

Almost surely, 2^61333640 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 61333640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72619200).

61333640 is an abundant number, since it is smaller than the sum of its proper divisors (83904760).

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

61333640 is a wasteful number, since it uses less digits than its factorization.

61333640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 606 (or 602 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 26.

The square root of 61333640 is about 7831.5796618562. The cubic root of 61333640 is about 394.3661039214.

Adding to 61333640 its reverse (4633316), we get a palindrome (65966956).

The spelling of 61333640 in words is "sixty-one million, three hundred thirty-three thousand, six hundred forty".