21167194019 has 4 divisors (see below), whose sum is σ = 21239437296. Its totient is φ = 21094950744.

The previous prime is 21167193959. The next prime is 21167194021. The reversal of 21167194019 is 91049176112.

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 21167194019 - 2²⁴ = 21150416803 is a prime.

It is a super-2 number, since 2×21167194019² (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 (21167194039) 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, 36121199 + ... + 36121784.

It is an arithmetic number, because the mean of its divisors is an integer number (5309859324).

Almost surely, 2^21167194019 is an apocalyptic number.

21167194019 is a deficient number, since it is larger than the sum of its proper divisors (72243277).

21167194019 is an equidigital number, since it uses as much as digits as its factorization.

21167194019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72243276.

The product of its (nonzero) digits is 27216, while the sum is 41.

The spelling of 21167194019 in words is "twenty-one billion, one hundred sixty-seven million, one hundred ninety-four thousand, nineteen".