21309876073 has 8 divisors (see below), whose sum is σ = 22360622400. Its totient is φ = 20269482288.

The previous prime is 21309876013. The next prime is 21309876109. The reversal of 21309876073 is 37067890312.

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 21309876073 - 2¹⁷ = 21309745001 is a prime.

It is a super-2 number, since 2×21309876073² (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 (21309876013) 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, 2583918 + ... + 2592151.

It is an arithmetic number, because the mean of its divisors is an integer number (2795077800).

Almost surely, 2^21309876073 is an apocalyptic number.

21309876073 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21309876073 is a deficient number, since it is larger than the sum of its proper divisors (1050746327).

21309876073 is a wasteful number, since it uses less digits than its factorization.

21309876073 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5176271.

The product of its (nonzero) digits is 381024, while the sum is 46.

The spelling of 21309876073 in words is "twenty-one billion, three hundred nine million, eight hundred seventy-six thousand, seventy-three".