51228649 has 2 divisors, whose sum is σ = 51228650. Its totient is φ = 51228648.

The previous prime is 51228643. The next prime is 51228673. The reversal of 51228649 is 94682215.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 35188624 + 16040025 = 5932^2 + 4005^2 .

It is a cyclic number.

It is not a de Polignac number, because 51228649 - 2¹³ = 51220457 is a prime.

It is not a weakly prime, because it can be changed into another prime (51228643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25614324 + 25614325.

It is an arithmetic number, because the mean of its divisors is an integer number (25614325).

Almost surely, 2^51228649 is an apocalyptic number.

It is an amenable number.

51228649 is a deficient number, since it is larger than the sum of its proper divisors (1).

51228649 is an equidigital number, since it uses as much as digits as its factorization.

51228649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34560, while the sum is 37.

The square root of 51228649 is about 7157.4191577691. The cubic root of 51228649 is about 371.3963525660.

It can be divided in two parts, 512 and 28649, that added together give a triangular number (29161 = T₂₄₁).

The spelling of 51228649 in words is "fifty-one million, two hundred twenty-eight thousand, six hundred forty-nine".