427721331643 has 4 divisors (see below), whose sum is σ = 428767105480. Its totient is φ = 426675557808.

The previous prime is 427721331637. The next prime is 427721331647. The reversal of 427721331643 is 346133127724.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-427721331643 is a prime.

It is a super-2 number, since 2×427721331643² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 427721331643.

It is not an unprimeable number, because it can be changed into a prime (427721331647) 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, 522886305 + ... + 522887122.

It is an arithmetic number, because the mean of its divisors is an integer number (107191776370).

Almost surely, 2^427721331643 is an apocalyptic number.

427721331643 is a deficient number, since it is larger than the sum of its proper divisors (1045773837).

427721331643 is a wasteful number, since it uses less digits than its factorization.

427721331643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1045773836.

The product of its digits is 508032, while the sum is 43.

The spelling of 427721331643 in words is "four hundred twenty-seven billion, seven hundred twenty-one million, three hundred thirty-one thousand, six hundred forty-three".