1645155257 has 2 divisors, whose sum is σ = 1645155258. Its totient is φ = 1645155256.

The previous prime is 1645155227. The next prime is 1645155287. The reversal of 1645155257 is 7525515461.

It is a balanced prime because it is at equal distance from previous prime (1645155227) and next prime (1645155287).

It can be written as a sum of positive squares in only one way, i.e., 1025344441 + 619810816 = 32021^2 + 24896^2 .

It is a cyclic number.

It is not a de Polignac number, because 1645155257 - 2¹² = 1645151161 is a prime.

It is not a weakly prime, because it can be changed into another prime (1645155227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 822577628 + 822577629.

It is an arithmetic number, because the mean of its divisors is an integer number (822577629).

Almost surely, 2^1645155257 is an apocalyptic number.

It is an amenable number.

1645155257 is a deficient number, since it is larger than the sum of its proper divisors (1).

1645155257 is an equidigital number, since it uses as much as digits as its factorization.

1645155257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 210000, while the sum is 41.

The square root of 1645155257 is about 40560.5135199248. The cubic root of 1645155257 is about 1180.5080779091.

The spelling of 1645155257 in words is "one billion, six hundred forty-five million, one hundred fifty-five thousand, two hundred fifty-seven".