51421321 has 8 divisors (see below), whose sum is σ = 60793920. Its totient is φ = 42555408.

The previous prime is 51421319. The next prime is 51421351. The reversal of 51421321 is 12312415.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 51421321 - 2¹ = 51421319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51421351) 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, 126451 + ... + 126856.

It is an arithmetic number, because the mean of its divisors is an integer number (7599240).

Almost surely, 2^51421321 is an apocalyptic number.

It is an amenable number.

51421321 is a deficient number, since it is larger than the sum of its proper divisors (9372599).

51421321 is a wasteful number, since it uses less digits than its factorization.

51421321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253343.

The product of its digits is 240, while the sum is 19.

The square root of 51421321 is about 7170.8661262082. The cubic root of 51421321 is about 371.8613798274.

Adding to 51421321 its reverse (12312415), we get a palindrome (63733736).

The spelling of 51421321 in words is "fifty-one million, four hundred twenty-one thousand, three hundred twenty-one".