212000021555 has 16 divisors (see below), whose sum is σ = 291246801600. Its totient is φ = 145119485952.

The previous prime is 212000021539. The next prime is 212000021567. The reversal of 212000021555 is 555120000212.

It is not a de Polignac number, because 212000021555 - 2⁴ = 212000021539 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 212000021555.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5228630 + ... + 5269019.

It is an arithmetic number, because the mean of its divisors is an integer number (18202925100).

Almost surely, 2^212000021555 is an apocalyptic number.

212000021555 is a deficient number, since it is larger than the sum of its proper divisors (79246780045).

212000021555 is a wasteful number, since it uses less digits than its factorization.

212000021555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10498238.

The product of its (nonzero) digits is 1000, while the sum is 23.

Adding to 212000021555 its reverse (555120000212), we get a palindrome (767120021767).

The spelling of 212000021555 in words is "two hundred twelve billion, twenty-one thousand, five hundred fifty-five".