53402240 has 64 divisors (see below), whose sum is σ = 128648520. Its totient is φ = 21196800.

The previous prime is 53402233. The next prime is 53402249. The reversal of 53402240 is 4220435.

It can be written as a sum of positive squares in 4 ways, for example, as 20866624 + 32535616 = 4568^2 + 5704^2 .

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

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (53402249) 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, 115610 + ... + 116070.

Almost surely, 2^53402240 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 53402240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (64324260).

53402240 is an abundant number, since it is smaller than the sum of its proper divisors (75246280).

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

53402240 is a wasteful number, since it uses less digits than its factorization.

53402240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661 (or 649 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 20.

The square root of 53402240 is about 7307.6836275252. The cubic root of 53402240 is about 376.5764509274.

Adding to 53402240 its reverse (4220435), we get a palindrome (57622675).

The spelling of 53402240 in words is "fifty-three million, four hundred two thousand, two hundred forty".