51220651 has 4 divisors (see below), whose sum is σ = 51266304. Its totient is φ = 51175000.

The previous prime is 51220639. The next prime is 51220703. The reversal of 51220651 is 15602215.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15602215 = 5 ⋅3120443.

It is a cyclic number.

It is not a de Polignac number, because 51220651 - 2⁹ = 51220139 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (51220621) 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, 21100 + ... + 23401.

It is an arithmetic number, because the mean of its divisors is an integer number (12816576).

Almost surely, 2^51220651 is an apocalyptic number.

51220651 is a deficient number, since it is larger than the sum of its proper divisors (45653).

51220651 is a wasteful number, since it uses less digits than its factorization.

51220651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45652.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 51220651 is about 7156.8604150144. The cubic root of 51220651 is about 371.3770236509.

Adding to 51220651 its reverse (15602215), we get a palindrome (66822866).

The spelling of 51220651 in words is "fifty-one million, two hundred twenty thousand, six hundred fifty-one".