20651515155 has 12 divisors (see below), whose sum is σ = 35795959680. Its totient is φ = 11014141392.

The previous prime is 20651515121. The next prime is 20651515217. The reversal of 20651515155 is 55151515602.

It is not a de Polignac number, because 20651515155 - 2¹³ = 20651506963 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 229461235 + ... + 229461324.

It is an arithmetic number, because the mean of its divisors is an integer number (2982996640).

Almost surely, 2^20651515155 is an apocalyptic number.

20651515155 is a deficient number, since it is larger than the sum of its proper divisors (15144444525).

20651515155 is a wasteful number, since it uses less digits than its factorization.

20651515155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 458922570 (or 458922567 counting only the distinct ones).

The product of its (nonzero) digits is 37500, while the sum is 36.

The spelling of 20651515155 in words is "twenty billion, six hundred fifty-one million, five hundred fifteen thousand, one hundred fifty-five".