20421325515 has 8 divisors (see below), whose sum is σ = 32674120848. Its totient is φ = 10891373600.

The previous prime is 20421325481. The next prime is 20421325523. The reversal of 20421325515 is 51552312402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20421325515 - 2⁹ = 20421325003 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 680710836 + ... + 680710865.

It is an arithmetic number, because the mean of its divisors is an integer number (4084265106).

Almost surely, 2^20421325515 is an apocalyptic number.

20421325515 is a deficient number, since it is larger than the sum of its proper divisors (12252795333).

20421325515 is a wasteful number, since it uses less digits than its factorization.

20421325515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1361421709.

The product of its (nonzero) digits is 12000, while the sum is 30.

Adding to 20421325515 its reverse (51552312402), we get a palindrome (71973637917).

The spelling of 20421325515 in words is "twenty billion, four hundred twenty-one million, three hundred twenty-five thousand, five hundred fifteen".