61191040 has 64 divisors (see below), whose sum is σ = 152681760. Its totient is φ = 23406592.

The previous prime is 61190989. The next prime is 61191043. The reversal of 61191040 is 4019116.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61191043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12642 + ... + 16798.

Almost surely, 2^61191040 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 61191040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76340880).

61191040 is an abundant number, since it is smaller than the sum of its proper divisors (91490720).

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

61191040 is a wasteful number, since it uses less digits than its factorization.

61191040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4199 (or 4187 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 22.

The square root of 61191040 is about 7822.4701980896. The cubic root of 61191040 is about 394.0602345488.

The spelling of 61191040 in words is "sixty-one million, one hundred ninety-one thousand, forty".