427321991681 has 8 divisors (see below), whose sum is σ = 460235251560. Its totient is φ = 394414780032.

The previous prime is 427321991623. The next prime is 427321991683. The reversal of 427321991681 is 186199123724.

It can be written as a sum of positive squares in 4 ways, for example, as 8143438081 + 419178553600 = 90241^2 + 647440^2 .

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

It is not a de Polignac number, because 427321991681 - 2³⁴ = 410142122497 is a prime.

It is a super-2 number, since 2×427321991681² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (427321991683) 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, 1364780 + ... + 1648413.

It is an arithmetic number, because the mean of its divisors is an integer number (57529406445).

Almost surely, 2^427321991681 is an apocalyptic number.

It is an amenable number.

427321991681 is a deficient number, since it is larger than the sum of its proper divisors (32913259879).

427321991681 is a wasteful number, since it uses less digits than its factorization.

427321991681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3024115.

The product of its digits is 1306368, while the sum is 53.

The spelling of 427321991681 in words is "four hundred twenty-seven billion, three hundred twenty-one million, nine hundred ninety-one thousand, six hundred eighty-one".