51778399 has 2 divisors, whose sum is σ = 51778400. Its totient is φ = 51778398.

The previous prime is 51778373. The next prime is 51778411. The reversal of 51778399 is 99387715.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 51778399 - 2¹⁷ = 51647327 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (51778319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 25889199 + 25889200.

It is an arithmetic number, because the mean of its divisors is an integer number (25889200).

Almost surely, 2^51778399 is an apocalyptic number.

51778399 is a deficient number, since it is larger than the sum of its proper divisors (1).

51778399 is an equidigital number, since it uses as much as digits as its factorization.

51778399 is an evil number, because the sum of its binary digits is even.

The product of its digits is 476280, while the sum is 49.

The square root of 51778399 is about 7195.7208811904. The cubic root of 51778399 is about 372.7201503317.

The spelling of 51778399 in words is "fifty-one million, seven hundred seventy-eight thousand, three hundred ninety-nine".