51212389 has 2 divisors, whose sum is σ = 51212390. Its totient is φ = 51212388.

The previous prime is 51212383. The next prime is 51212401. The reversal of 51212389 is 98321215.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 45292900 + 5919489 = 6730^2 + 2433^2 .

It is a cyclic number.

It is not a de Polignac number, because 51212389 - 2⁷ = 51212261 is a prime.

It is equal to p_3069409 and since 51212389 and 3069409 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 51212389.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51212383) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25606194 + 25606195.

It is an arithmetic number, because the mean of its divisors is an integer number (25606195).

Almost surely, 2^51212389 is an apocalyptic number.

It is an amenable number.

51212389 is a deficient number, since it is larger than the sum of its proper divisors (1).

51212389 is an equidigital number, since it uses as much as digits as its factorization.

51212389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 31.

The square root of 51212389 is about 7156.2831833292. The cubic root of 51212389 is about 371.3570546091.

The spelling of 51212389 in words is "fifty-one million, two hundred twelve thousand, three hundred eighty-nine".