2161254665420 has 12 divisors (see below), whose sum is σ = 4538634797424. Its totient is φ = 864501866160.

The previous prime is 2161254665407. The next prime is 2161254665441. The reversal of 2161254665420 is 245664521612.

It is a super-2 number, since 2×2161254665420² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54031366616 + ... + 54031366655.

It is an arithmetic number, because the mean of its divisors is an integer number (378219566452).

Almost surely, 2^{2161254665420} is an apocalyptic number.

2161254665420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2161254665420 is an abundant number, since it is smaller than the sum of its proper divisors (2377380132004).

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

2161254665420 is a wasteful number, since it uses less digits than its factorization.

2161254665420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 108062733280 (or 108062733278 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 44.

The spelling of 2161254665420 in words is "two trillion, one hundred sixty-one billion, two hundred fifty-four million, six hundred sixty-five thousand, four hundred twenty".