1256020513 has 8 divisors (see below), whose sum is σ = 1370465856. Its totient is φ = 1141618800.

The previous prime is 1256020511. The next prime is 1256020523. The reversal of 1256020513 is 3150206521.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1256020513 - 2¹ = 1256020511 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1256020511) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 89620 + ... + 102682.

It is an arithmetic number, because the mean of its divisors is an integer number (171308232).

Almost surely, 2^1256020513 is an apocalyptic number.

It is an amenable number.

1256020513 is a deficient number, since it is larger than the sum of its proper divisors (114445343).

1256020513 is a wasteful number, since it uses less digits than its factorization.

1256020513 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21815.

The product of its (nonzero) digits is 1800, while the sum is 25.

The square root of 1256020513 is about 35440.3796960473. The cubic root of 1256020513 is about 1078.9440161315.

The spelling of 1256020513 in words is "one billion, two hundred fifty-six million, twenty thousand, five hundred thirteen".