2055121721 has 16 divisors (see below), whose sum is σ = 2208061440. Its totient is φ = 1905845760.

The previous prime is 2055121711. The next prime is 2055121741. The reversal of 2055121721 is 1271215502.

It is a cyclic number.

It is not a de Polignac number, because 2055121721 - 2¹⁸ = 2054859577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2055121711) 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, 813941 + ... + 816461.

It is an arithmetic number, because the mean of its divisors is an integer number (138003840).

Almost surely, 2^2055121721 is an apocalyptic number.

It is an amenable number.

2055121721 is a deficient number, since it is larger than the sum of its proper divisors (152939719).

2055121721 is a wasteful number, since it uses less digits than its factorization.

2055121721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3224.

The product of its (nonzero) digits is 1400, while the sum is 26.

The square root of 2055121721 is about 45333.4503540156. The cubic root of 2055121721 is about 1271.3911473844.

The spelling of 2055121721 in words is "two billion, fifty-five million, one hundred twenty-one thousand, seven hundred twenty-one".