51004021 has 4 divisors (see below), whose sum is σ = 52649344. Its totient is φ = 49358700.

The previous prime is 51004013. The next prime is 51004027. The reversal of 51004021 is 12040015.

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.

It is a cyclic number.

It is not a de Polignac number, because 51004021 - 2³ = 51004013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 51003992 and 51004010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (51004027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 822615 + ... + 822676.

It is an arithmetic number, because the mean of its divisors is an integer number (13162336).

Almost surely, 2^51004021 is an apocalyptic number.

It is an amenable number.

51004021 is a deficient number, since it is larger than the sum of its proper divisors (1645323).

51004021 is a wasteful number, since it uses less digits than its factorization.

51004021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1645322.

The product of its (nonzero) digits is 40, while the sum is 13.

The square root of 51004021 is about 7141.7099493049. The cubic root of 51004021 is about 370.8527228117.

Adding to 51004021 its reverse (12040015), we get a palindrome (63044036).

The spelling of 51004021 in words is "fifty-one million, four thousand, twenty-one".