1256521010 has 16 divisors (see below), whose sum is σ = 2262943872. Its totient is φ = 502340400.

The previous prime is 1256521003. The next prime is 1256521081. The reversal of 1256521010 is 101256521.

It is a happy number.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13226 + ... + 51845.

It is an arithmetic number, because the mean of its divisors is an integer number (141433992).

Almost surely, 2^1256521010 is an apocalyptic number.

1256521010 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1256521010 is a deficient number, since it is larger than the sum of its proper divisors (1006422862).

1256521010 is a wasteful number, since it uses less digits than its factorization.

1256521010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67009.

The product of its (nonzero) digits is 600, while the sum is 23.

The square root of 1256521010 is about 35447.4401050344. The cubic root of 1256521010 is about 1079.0873090492.

Adding to 1256521010 its reverse (101256521), we get a palindrome (1357777531).

The spelling of 1256521010 in words is "one billion, two hundred fifty-six million, five hundred twenty-one thousand, ten".