1928555257 has 2 divisors, whose sum is σ = 1928555258. Its totient is φ = 1928555256.

The previous prime is 1928555249. The next prime is 1928555263. The reversal of 1928555257 is 7525558291.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1840495801 + 88059456 = 42901^2 + 9384^2 .

It is a cyclic number.

It is not a de Polignac number, because 1928555257 - 2³ = 1928555249 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1928555257.

It is not a weakly prime, because it can be changed into another prime (1928555207) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 964277628 + 964277629.

It is an arithmetic number, because the mean of its divisors is an integer number (964277629).

Almost surely, 2^1928555257 is an apocalyptic number.

It is an amenable number.

1928555257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1928555257 is an equidigital number, since it uses as much as digits as its factorization.

1928555257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1260000, while the sum is 49.

The square root of 1928555257 is about 43915.3191608578. The cubic root of 1928555257 is about 1244.7363208843.

The spelling of 1928555257 in words is "one billion, nine hundred twenty-eight million, five hundred fifty-five thousand, two hundred fifty-seven".