21870342143 has 16 divisors (see below), whose sum is σ = 24641003520. Its totient is φ = 19259749344.

The previous prime is 21870342113. The next prime is 21870342161. The reversal of 21870342143 is 34124307812.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21870342143 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21870342113) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19028 + ... + 210006.

It is an arithmetic number, because the mean of its divisors is an integer number (1540062720).

Almost surely, 2^21870342143 is an apocalyptic number.

21870342143 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

21870342143 is a deficient number, since it is larger than the sum of its proper divisors (2770661377).

21870342143 is a wasteful number, since it uses less digits than its factorization.

21870342143 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 191398.

The product of its (nonzero) digits is 32256, while the sum is 35.

Adding to 21870342143 its reverse (34124307812), we get a palindrome (55994649955).

The spelling of 21870342143 in words is "twenty-one billion, eight hundred seventy million, three hundred forty-two thousand, one hundred forty-three".