20451230515 has 4 divisors (see below), whose sum is σ = 24541476624. Its totient is φ = 16360984408.

The previous prime is 20451230479. The next prime is 20451230543. The reversal of 20451230515 is 51503215402.

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 20451230515 - 2¹⁵ = 20451197747 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2045123047 + ... + 2045123056.

It is an arithmetic number, because the mean of its divisors is an integer number (6135369156).

Almost surely, 2^20451230515 is an apocalyptic number.

20451230515 is a deficient number, since it is larger than the sum of its proper divisors (4090246109).

20451230515 is an equidigital number, since it uses as much as digits as its factorization.

20451230515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4090246108.

The product of its (nonzero) digits is 6000, while the sum is 28.

Adding to 20451230515 its reverse (51503215402), we get a palindrome (71954445917).

The spelling of 20451230515 in words is "twenty billion, four hundred fifty-one million, two hundred thirty thousand, five hundred fifteen".