61957440 has 224 divisors, whose sum is σ = 223845120. Its totient is φ = 16128000.

The previous prime is 61957429. The next prime is 61957447. The reversal of 61957440 is 4475916.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

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

It is a junction number, because it is equal to n+sod(n) for n = 61957395 and 61957404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61957447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 613390 + ... + 613490.

Almost surely, 2^61957440 is an apocalyptic number.

61957440 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61957440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111922560).

61957440 is an abundant number, since it is smaller than the sum of its proper divisors (161887680).

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

61957440 is a wasteful number, since it uses less digits than its factorization.

61957440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 61957440 is about 7871.3048473554. The cubic root of 61957440 is about 395.6985768684.

The spelling of 61957440 in words is "sixty-one million, nine hundred fifty-seven thousand, four hundred forty".