21145364403 has 4 divisors (see below), whose sum is σ = 28193819208. Its totient is φ = 14096909600.

The previous prime is 21145364381. The next prime is 21145364419. The reversal of 21145364403 is 30446354112.

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 21145364403 - 2¹⁸ = 21145102259 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21145364453) 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, 3524227398 + ... + 3524227403.

It is an arithmetic number, because the mean of its divisors is an integer number (7048454802).

Almost surely, 2^21145364403 is an apocalyptic number.

21145364403 is a deficient number, since it is larger than the sum of its proper divisors (7048454805).

21145364403 is an equidigital number, since it uses as much as digits as its factorization.

21145364403 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7048454804.

The product of its (nonzero) digits is 34560, while the sum is 33.

The spelling of 21145364403 in words is "twenty-one billion, one hundred forty-five million, three hundred sixty-four thousand, four hundred three".