21854841137 has 4 divisors (see below), whose sum is σ = 22118152560. Its totient is φ = 21591529716.

The previous prime is 21854841133. The next prime is 21854841149. The reversal of 21854841137 is 73114845812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21854841137 - 2² = 21854841133 is a prime.

It is a super-2 number, since 2×21854841137² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21854841133) 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, 131655587 + ... + 131655752.

It is an arithmetic number, because the mean of its divisors is an integer number (5529538140).

Almost surely, 2^21854841137 is an apocalyptic number.

It is an amenable number.

21854841137 is a deficient number, since it is larger than the sum of its proper divisors (263311423).

21854841137 is an equidigital number, since it uses as much as digits as its factorization.

21854841137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263311422.

The product of its digits is 215040, while the sum is 44.

The spelling of 21854841137 in words is "twenty-one billion, eight hundred fifty-four million, eight hundred forty-one thousand, one hundred thirty-seven".