205215160106021 has 16 divisors (see below), whose sum is σ = 221419112302080. Its totient is φ = 189071077866240.

The previous prime is 205215160106003. The next prime is 205215160106027. The reversal of 205215160106021 is 120601061512502.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205215160106021 is a prime.

It is a super-2 number, since 2×205215160106021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205215160106027) 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, 34818020 + ... + 40283058.

It is an arithmetic number, because the mean of its divisors is an integer number (13838694518880).

Almost surely, 2^{205215160106021} is an apocalyptic number.

It is an amenable number.

205215160106021 is a deficient number, since it is larger than the sum of its proper divisors (16203952196059).

205215160106021 is a wasteful number, since it uses less digits than its factorization.

205215160106021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5470516.

The product of its (nonzero) digits is 7200, while the sum is 32.

The spelling of 205215160106021 in words is "two hundred five trillion, two hundred fifteen billion, one hundred sixty million, one hundred six thousand, twenty-one".