20515034399 has 4 divisors (see below), whose sum is σ = 20515324536. Its totient is φ = 20514744264.

The previous prime is 20515034383. The next prime is 20515034411. The reversal of 20515034399 is 99343051502.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 20515034399 - 2⁴ = 20515034383 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20515034899) 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, 38012 + ... + 206094.

It is an arithmetic number, because the mean of its divisors is an integer number (5128831134).

Almost surely, 2^20515034399 is an apocalyptic number.

20515034399 is a deficient number, since it is larger than the sum of its proper divisors (290137).

20515034399 is a wasteful number, since it uses less digits than its factorization.

20515034399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290136.

The product of its (nonzero) digits is 145800, while the sum is 41.

The spelling of 20515034399 in words is "twenty billion, five hundred fifteen million, thirty-four thousand, three hundred ninety-nine".