2171851867020 has 48 divisors (see below), whose sum is σ = 6634020250368. Its totient is φ = 526509543360.

The previous prime is 2171851867013. The next prime is 2171851867021. The reversal of 2171851867020 is 207681581712.

It is not an unprimeable number, because it can be changed into a prime (2171851867021) 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, 1645341664 + ... + 1645342983.

It is an arithmetic number, because the mean of its divisors is an integer number (138208755216).

Almost surely, 2^{2171851867020} is an apocalyptic number.

2171851867020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2171851867020 is an abundant number, since it is smaller than the sum of its proper divisors (4462168383348).

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

2171851867020 is a wasteful number, since it uses less digits than its factorization.

2171851867020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3290684670 (or 3290684668 counting only the distinct ones).

The product of its (nonzero) digits is 376320, while the sum is 48.

The spelling of 2171851867020 in words is "two trillion, one hundred seventy-one billion, eight hundred fifty-one million, eight hundred sixty-seven thousand, twenty".