21193456619 has 4 divisors (see below), whose sum is σ = 21491956080. Its totient is φ = 20894957160.

The previous prime is 21193456607. The next prime is 21193456639. The reversal of 21193456619 is 91665439112.

It is a happy number.

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 21193456619 - 2⁸ = 21193456363 is a prime.

It is a super-2 number, since 2×21193456619² (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 (21193456639) 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, 149249624 + ... + 149249765.

It is an arithmetic number, because the mean of its divisors is an integer number (5372989020).

Almost surely, 2^21193456619 is an apocalyptic number.

21193456619 is a deficient number, since it is larger than the sum of its proper divisors (298499461).

21193456619 is an equidigital number, since it uses as much as digits as its factorization.

21193456619 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 298499460.

The product of its digits is 349920, while the sum is 47.

The spelling of 21193456619 in words is "twenty-one billion, one hundred ninety-three million, four hundred fifty-six thousand, six hundred nineteen".