55352021 has 4 divisors (see below), whose sum is σ = 55556544. Its totient is φ = 55147500.

The previous prime is 55351987. The next prime is 55352027. The reversal of 55352021 is 12025355.

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: 12025355 = 5 ⋅2405071.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-55352021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55352027) 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, 101855 + ... + 102396.

It is an arithmetic number, because the mean of its divisors is an integer number (13889136).

Almost surely, 2^55352021 is an apocalyptic number.

It is an amenable number.

55352021 is a deficient number, since it is larger than the sum of its proper divisors (204523).

55352021 is a wasteful number, since it uses less digits than its factorization.

55352021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204522.

The product of its (nonzero) digits is 1500, while the sum is 23.

The square root of 55352021 is about 7439.8938836518. The cubic root of 55352021 is about 381.1048661587.

Adding to 55352021 its reverse (12025355), we get a palindrome (67377376).

The spelling of 55352021 in words is "fifty-five million, three hundred fifty-two thousand, twenty-one".