53021840 has 20 divisors (see below), whose sum is σ = 123275964. Its totient is φ = 21208704.

The previous prime is 53021833. The next prime is 53021863. The reversal of 53021840 is 4812035.

It can be written as a sum of positive squares in 2 ways, for example, as 23775376 + 29246464 = 4876^2 + 5408^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-2 number, since 2×53021840² = 5622631033971200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 331307 + ... + 331466.

Almost surely, 2^53021840 is an apocalyptic number.

It is an amenable number.

53021840 is an abundant number, since it is smaller than the sum of its proper divisors (70254124).

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

53021840 is a wasteful number, since it uses less digits than its factorization.

53021840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662786 (or 662780 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 53021840 is about 7281.6097121447. The cubic root of 53021840 is about 375.6801641107.

Adding to 53021840 its reverse (4812035), we get a palindrome (57833875).

The spelling of 53021840 in words is "fifty-three million, twenty-one thousand, eight hundred forty".