42847157818621 has 4 divisors (see below), whose sum is σ = 46143093035452. Its totient is φ = 39551222601792.

The previous prime is 42847157818603. The next prime is 42847157818649. The reversal of 42847157818621 is 12681875174824.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25034621978521 + 17812535840100 = 5003461^2 + 4220490^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42847157818621 is a prime.

It is a super-2 number, since 2×42847157818621² (a number of 28 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 (42847157818651) 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, 1647967608396 + ... + 1647967608421.

It is an arithmetic number, because the mean of its divisors is an integer number (11535773258863).

Almost surely, 2^{42847157818621} is an apocalyptic number.

It is an amenable number.

42847157818621 is a deficient number, since it is larger than the sum of its proper divisors (3295935216831).

42847157818621 is a wasteful number, since it uses less digits than its factorization.

42847157818621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3295935216830.

The product of its digits is 48168960, while the sum is 64.

The spelling of 42847157818621 in words is "forty-two trillion, eight hundred forty-seven billion, one hundred fifty-seven million, eight hundred eighteen thousand, six hundred twenty-one".