51522021 has 8 divisors (see below), whose sum is σ = 76328960. Its totient is φ = 34347996.

The previous prime is 51522007. The next prime is 51522043. The reversal of 51522021 is 12022515.

It is not a de Polignac number, because 51522021 - 2¹¹ = 51519973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51521985 and 51522003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51522071) 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, 954085 + ... + 954138.

It is an arithmetic number, because the mean of its divisors is an integer number (9541120).

Almost surely, 2^51522021 is an apocalyptic number.

It is an amenable number.

51522021 is a deficient number, since it is larger than the sum of its proper divisors (24806939).

51522021 is a wasteful number, since it uses less digits than its factorization.

51522021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908232 (or 1908226 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 18.

The square root of 51522021 is about 7177.8841589984. The cubic root of 51522021 is about 372.1039641783.

Adding to 51522021 its reverse (12022515), we get a palindrome (63544536).

The spelling of 51522021 in words is "fifty-one million, five hundred twenty-two thousand, twenty-one".