20177644231 has 4 divisors (see below), whose sum is σ = 20187999000. Its totient is φ = 20167289464.

The previous prime is 20177644189. The next prime is 20177644241. The reversal of 20177644231 is 13244677102.

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

It is a cyclic number.

It is not a de Polignac number, because 20177644231 - 2⁹ = 20177643719 is a prime.

It is a super-2 number, since 2×20177644231² (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 (20177644241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5174461 + ... + 5178358.

It is an arithmetic number, because the mean of its divisors is an integer number (5046999750).

Almost surely, 2^20177644231 is an apocalyptic number.

20177644231 is a deficient number, since it is larger than the sum of its proper divisors (10354769).

20177644231 is a wasteful number, since it uses less digits than its factorization.

20177644231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10354768.

The product of its (nonzero) digits is 56448, while the sum is 37.

The spelling of 20177644231 in words is "twenty billion, one hundred seventy-seven million, six hundred forty-four thousand, two hundred thirty-one".