21858354329 has 8 divisors (see below), whose sum is σ = 25035643008. Its totient is φ = 18694732320.

The previous prime is 21858354307. The next prime is 21858354373. The reversal of 21858354329 is 92345385812.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21858354329 - 2⁸ = 21858354073 is a prime.

It is a super-2 number, since 2×21858354329² (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 (21858357329) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3413237 + ... + 3419634.

It is an arithmetic number, because the mean of its divisors is an integer number (3129455376).

Almost surely, 2^21858354329 is an apocalyptic number.

It is an amenable number.

21858354329 is a deficient number, since it is larger than the sum of its proper divisors (3177288679).

21858354329 is an equidigital number, since it uses as much as digits as its factorization.

21858354329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6833335.

The product of its digits is 2073600, while the sum is 50.

The spelling of 21858354329 in words is "twenty-one billion, eight hundred fifty-eight million, three hundred fifty-four thousand, three hundred twenty-nine".