21395801345 has 8 divisors (see below), whose sum is σ = 26159395176. Its totient is φ = 16793685376.

The previous prime is 21395801341. The next prime is 21395801369. The reversal of 21395801345 is 54310859312.

It can be written as a sum of positive squares in 4 ways, for example, as 163814401 + 21231986944 = 12799^2 + 145712^2 .

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 21395801345 - 2² = 21395801341 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21395801341) 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, 40369172 + ... + 40369701.

It is an arithmetic number, because the mean of its divisors is an integer number (3269924397).

Almost surely, 2^21395801345 is an apocalyptic number.

It is an amenable number.

21395801345 is a deficient number, since it is larger than the sum of its proper divisors (4763593831).

21395801345 is an equidigital number, since it uses as much as digits as its factorization.

21395801345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80738931.

The product of its (nonzero) digits is 129600, while the sum is 41.

The spelling of 21395801345 in words is "twenty-one billion, three hundred ninety-five million, eight hundred one thousand, three hundred forty-five".