61321040 has 80 divisors (see below), whose sum is σ = 164721600. Its totient is φ = 20981760.

The previous prime is 61321021. The next prime is 61321049. The reversal of 61321040 is 4012316.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (17).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61321049) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12911 + ... + 17009.

It is an arithmetic number, because the mean of its divisors is an integer number (2059020).

Almost surely, 2^61321040 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 61321040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82360800).

61321040 is an abundant number, since it is smaller than the sum of its proper divisors (103400560).

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

61321040 is a wasteful number, since it uses less digits than its factorization.

61321040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4140 (or 4134 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 61321040 is about 7830.7751851269. The cubic root of 61321040 is about 394.3390967020.

Adding to 61321040 its reverse (4012316), we get a palindrome (65333356).

The spelling of 61321040 in words is "sixty-one million, three hundred twenty-one thousand, forty".