61523840 has 128 divisors (see below), whose sum is σ = 173905920. Its totient is φ = 20367360.

The previous prime is 61523837. The next prime is 61523849. The reversal of 61523840 is 4832516.

It is a tau number, because it is divible by the number of its divisors (128).

It is a hoax number, since the sum of its digits (29) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61523849) 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, 138659 + ... + 139101.

It is an arithmetic number, because the mean of its divisors is an integer number (1358640).

Almost surely, 2^61523840 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 61523840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (86952960).

61523840 is an abundant number, since it is smaller than the sum of its proper divisors (112382080).

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

61523840 is a wasteful number, since it uses less digits than its factorization.

61523840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 500 (or 488 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The square root of 61523840 is about 7843.7134062891. The cubic root of 61523840 is about 394.7733357481.

The spelling of 61523840 in words is "sixty-one million, five hundred twenty-three thousand, eight hundred forty".