1256505133730 has 64 divisors (see below), whose sum is σ = 2985663566592. Its totient is φ = 368600432640.

The previous prime is 1256505133729. The next prime is 1256505133753. The reversal of 1256505133730 is 373315056521.

It is a happy number.

It is a super-3 number, since 3×1256505133730³ (a number of 37 digits) contains 333 as substring.

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 31 ways as a sum of consecutive naturals, for example, 47981759 + ... + 48007938.

It is an arithmetic number, because the mean of its divisors is an integer number (46650993228).

Almost surely, 2^{1256505133730} is an apocalyptic number.

1256505133730 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1256505133730 is an abundant number, since it is smaller than the sum of its proper divisors (1729158432862).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1256505133730 is a wasteful number, since it uses less digits than its factorization.

1256505133730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95989739.

The product of its (nonzero) digits is 283500, while the sum is 41.

The spelling of 1256505133730 in words is "one trillion, two hundred fifty-six billion, five hundred five million, one hundred thirty-three thousand, seven hundred thirty".