51473221 has 2 divisors, whose sum is σ = 51473222. Its totient is φ = 51473220.

The previous prime is 51473183. The next prime is 51473267. The reversal of 51473221 is 12237415.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39125025 + 12348196 = 6255^2 + 3514^2 .

It is a cyclic number.

It is not a de Polignac number, because 51473221 - 2¹⁷ = 51342149 is a prime.

It is a super-2 number, since 2×51473221² = 5298984960229682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51473291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25736610 + 25736611.

It is an arithmetic number, because the mean of its divisors is an integer number (25736611).

Almost surely, 2^51473221 is an apocalyptic number.

It is an amenable number.

51473221 is a deficient number, since it is larger than the sum of its proper divisors (1).

51473221 is an equidigital number, since it uses as much as digits as its factorization.

51473221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1680, while the sum is 25.

The square root of 51473221 is about 7174.4840232591. The cubic root of 51473221 is about 371.9864454344.

The spelling of 51473221 in words is "fifty-one million, four hundred seventy-three thousand, two hundred twenty-one".