53991720 has 96 divisors (see below), whose sum is σ = 179262720. Its totient is φ = 14087040.

The previous prime is 53991719. The next prime is 53991809. The reversal of 53991720 is 2719935.

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

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15325 + ... + 18515.

It is an arithmetic number, because the mean of its divisors is an integer number (1867320).

Almost surely, 2^53991720 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 53991720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89631360).

53991720 is an abundant number, since it is smaller than the sum of its proper divisors (125271000).

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

53991720 is a wasteful number, since it uses less digits than its factorization.

53991720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3255 (or 3248 counting only the distinct ones).

The product of its (nonzero) digits is 17010, while the sum is 36.

The square root of 53991720 is about 7347.9058241107. The cubic root of 53991720 is about 377.9569951915.

It can be divided in two parts, 5 and 3991720, that added together give a triangular number (3991725 = T₂₈₂₅).

The spelling of 53991720 in words is "fifty-three million, nine hundred ninety-one thousand, seven hundred twenty".