2121615662656 has 56 divisors (see below), whose sum is σ = 4872426648320. Its totient is φ = 897754171392.

The previous prime is 2121615662599. The next prime is 2121615662659. The reversal of 2121615662656 is 6562665161212.

It is a tau number, because it is divible by the number of its divisors (56).

It is not an unprimeable number, because it can be changed into a prime (2121615662659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29937705 + ... + 30008488.

It is an arithmetic number, because the mean of its divisors is an integer number (87007618720).

Almost surely, 2^{2121615662656} is an apocalyptic number.

It is an amenable number.

2121615662656 is an abundant number, since it is smaller than the sum of its proper divisors (2750810985664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2121615662656 is an equidigital number, since it uses as much as digits as its factorization.

2121615662656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59946291 (or 59946281 counting only the distinct ones).

The product of its digits is 1555200, while the sum is 49.

The spelling of 2121615662656 in words is "two trillion, one hundred twenty-one billion, six hundred fifteen million, six hundred sixty-two thousand, six hundred fifty-six".