21150302345 has 4 divisors (see below), whose sum is σ = 25380362820. Its totient is φ = 16920241872.

The previous prime is 21150302311. The next prime is 21150302347. The reversal of 21150302345 is 54320305112.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 16830132361 + 4320169984 = 129731^2 + 65728^2 .

It is a cyclic number.

It is not a de Polignac number, because 21150302345 - 2³⁴ = 3970433161 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21150302347) 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, 2115030230 + ... + 2115030239.

It is an arithmetic number, because the mean of its divisors is an integer number (6345090705).

Almost surely, 2^21150302345 is an apocalyptic number.

It is an amenable number.

21150302345 is a deficient number, since it is larger than the sum of its proper divisors (4230060475).

21150302345 is an equidigital number, since it uses as much as digits as its factorization.

21150302345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4230060474.

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 21150302345 its reverse (54320305112), we get a palindrome (75470607457).

The spelling of 21150302345 in words is "twenty-one billion, one hundred fifty million, three hundred two thousand, three hundred forty-five".