51205069 has 2 divisors, whose sum is σ = 51205070. Its totient is φ = 51205068.

The previous prime is 51205031. The next prime is 51205073. The reversal of 51205069 is 96050215.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49140100 + 2064969 = 7010^2 + 1437^2 .

It is a cyclic number.

It is not a de Polignac number, because 51205069 - 2¹⁹ = 50680781 is a prime.

It is a super-2 number, since 2×51205069² = 5243918182589522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51200069) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25602534 + 25602535.

It is an arithmetic number, because the mean of its divisors is an integer number (25602535).

Almost surely, 2^51205069 is an apocalyptic number.

It is an amenable number.

51205069 is a deficient number, since it is larger than the sum of its proper divisors (1).

51205069 is an equidigital number, since it uses as much as digits as its factorization.

51205069 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2700, while the sum is 28.

The square root of 51205069 is about 7155.7717263758. The cubic root of 51205069 is about 371.3393605627.

It can be divided in two parts, 51 and 205069, that added together give a triangular number (205120 = T₆₄₀).

The spelling of 51205069 in words is "fifty-one million, two hundred five thousand, sixty-nine".