61371640 has 64 divisors (see below), whose sum is σ = 152241120. Its totient is φ = 22080000.

The previous prime is 61371637. The next prime is 61371647. The reversal of 61371640 is 4617316.

It is a Smith number, since the sum of its digits (28) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 61371599 and 61371608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61371647) 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, 43750 + ... + 45130.

Almost surely, 2^61371640 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 61371640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76120560).

61371640 is an abundant number, since it is smaller than the sum of its proper divisors (90869480).

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

61371640 is a wasteful number, since it uses less digits than its factorization.

61371640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1504 (or 1500 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 61371640 is about 7834.0053612440. The cubic root of 61371640 is about 394.4475318735.

Adding to 61371640 its reverse (4617316), we get a palindrome (65988956).

It can be divided in two parts, 6137 and 1640, that added together give a palindrome (7777).

The spelling of 61371640 in words is "sixty-one million, three hundred seventy-one thousand, six hundred forty".