12858156781 has 4 divisors (see below), whose sum is σ = 13272936064. Its totient is φ = 12443377500.

The previous prime is 12858156763. The next prime is 12858156803. The reversal of 12858156781 is 18765185821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18765185821 = 19 ⋅987641359.

It is a cyclic number.

It is not a de Polignac number, because 12858156781 - 2³¹ = 10710673133 is a prime.

It is a super-2 number, since 2×12858156781² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12858156761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 207389595 + ... + 207389656.

It is an arithmetic number, because the mean of its divisors is an integer number (3318234016).

Almost surely, 2^12858156781 is an apocalyptic number.

It is an amenable number.

12858156781 is a deficient number, since it is larger than the sum of its proper divisors (414779283).

12858156781 is an equidigital number, since it uses as much as digits as its factorization.

12858156781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414779282.

The product of its digits is 1075200, while the sum is 52.

The spelling of 12858156781 in words is "twelve billion, eight hundred fifty-eight million, one hundred fifty-six thousand, seven hundred eighty-one".