1257538705 has 24 divisors (see below), whose sum is σ = 1607226048. Its totient is φ = 944379648.

The previous prime is 1257538697. The next prime is 1257538747. The reversal of 1257538705 is 5078357521.

It is not a de Polignac number, because 1257538705 - 2³ = 1257538697 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 702822 + ... + 704608.

It is an arithmetic number, because the mean of its divisors is an integer number (66967752).

Almost surely, 2^1257538705 is an apocalyptic number.

It is an amenable number.

1257538705 is a deficient number, since it is larger than the sum of its proper divisors (349687343).

1257538705 is a wasteful number, since it uses less digits than its factorization.

1257538705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2313 (or 2296 counting only the distinct ones).

The product of its (nonzero) digits is 294000, while the sum is 43.

The square root of 1257538705 is about 35461.7921853930. The cubic root of 1257538705 is about 1079.3785590959.

The spelling of 1257538705 in words is "one billion, two hundred fifty-seven million, five hundred thirty-eight thousand, seven hundred five".