540665421638 has 4 divisors (see below), whose sum is σ = 810998132460. Its totient is φ = 270332710818.

The previous prime is 540665421613. The next prime is 540665421671. The reversal of 540665421638 is 836124566045.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 135166355408 + ... + 135166355411.

It is an arithmetic number, because the mean of its divisors is an integer number (202749533115).

Almost surely, 2^540665421638 is an apocalyptic number.

540665421638 is a deficient number, since it is larger than the sum of its proper divisors (270332710822).

540665421638 is a wasteful number, since it uses less digits than its factorization.

540665421638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270332710821.

The product of its (nonzero) digits is 4147200, while the sum is 50.

The spelling of 540665421638 in words is "five hundred forty billion, six hundred sixty-five million, four hundred twenty-one thousand, six hundred thirty-eight".