51394649 has 2 divisors, whose sum is σ = 51394650. Its totient is φ = 51394648.

The previous prime is 51394643. The next prime is 51394657. The reversal of 51394649 is 94649315.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 47265625 + 4129024 = 6875^2 + 2032^2 .

It is a cyclic number.

It is not a de Polignac number, because 51394649 - 2⁴ = 51394633 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (51394643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25697324 + 25697325.

It is an arithmetic number, because the mean of its divisors is an integer number (25697325).

Almost surely, 2^51394649 is an apocalyptic number.

It is an amenable number.

51394649 is a deficient number, since it is larger than the sum of its proper divisors (1).

51394649 is an equidigital number, since it uses as much as digits as its factorization.

51394649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116640, while the sum is 41.

The square root of 51394649 is about 7169.0061375340. The cubic root of 51394649 is about 371.7970744519.

It can be divided in two parts, 5 and 1394649, that multiplied together give a triangular number (6973245 = T₃₇₃₄).

The spelling of 51394649 in words is "fifty-one million, three hundred ninety-four thousand, six hundred forty-nine".