53020021 has 4 divisors (see below), whose sum is σ = 53401600. Its totient is φ = 52638444.

The previous prime is 53020003. The next prime is 53020039. The reversal of 53020021 is 12002035.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12002035 = 5 ⋅2400407.

It is an interprime number because it is at equal distance from previous prime (53020003) and next prime (53020039).

It is a cyclic number.

It is not a de Polignac number, because 53020021 - 2⁷ = 53019893 is a prime.

It is a super-2 number, since 2×53020021² = 5622245253680882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 53019983 and 53020010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (53020081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 190581 + ... + 190858.

It is an arithmetic number, because the mean of its divisors is an integer number (13350400).

Almost surely, 2^53020021 is an apocalyptic number.

It is an amenable number.

53020021 is a deficient number, since it is larger than the sum of its proper divisors (381579).

53020021 is a wasteful number, since it uses less digits than its factorization.

53020021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 381578.

The product of its (nonzero) digits is 60, while the sum is 13.

The square root of 53020021 is about 7281.4848073727. The cubic root of 53020021 is about 375.6758679563.

Adding to 53020021 its reverse (12002035), we get a palindrome (65022056).

The spelling of 53020021 in words is "fifty-three million, twenty thousand, twenty-one".