20828620815 has 16 divisors (see below), whose sum is σ = 34034853888. Its totient is φ = 10872244256.

The previous prime is 20828620811. The next prime is 20828620817. The reversal of 20828620815 is 51802682802.

It is a cyclic number.

It is not a de Polignac number, because 20828620815 - 2² = 20828620811 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20828620811) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14771367 + ... + 14772776.

It is an arithmetic number, because the mean of its divisors is an integer number (2127178368).

Almost surely, 2^20828620815 is an apocalyptic number.

20828620815 is a deficient number, since it is larger than the sum of its proper divisors (13206233073).

20828620815 is a wasteful number, since it uses less digits than its factorization.

20828620815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29544198.

The product of its (nonzero) digits is 122880, while the sum is 42.

The spelling of 20828620815 in words is "twenty billion, eight hundred twenty-eight million, six hundred twenty thousand, eight hundred fifteen".