212920831851 has 72 divisors (see below), whose sum is σ = 358904674224. Its totient is φ = 111900821760.

The previous prime is 212920831831. The next prime is 212920831853. The reversal of 212920831851 is 158138029212.

It is not a de Polignac number, because 212920831851 - 2⁵ = 212920831819 is a prime.

It is a super-2 number, since 2×212920831851² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (212920831853) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 6866041 + ... + 6896981.

It is an arithmetic number, because the mean of its divisors is an integer number (4984787142).

Almost surely, 2^212920831851 is an apocalyptic number.

212920831851 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

212920831851 is a deficient number, since it is larger than the sum of its proper divisors (145983842373).

212920831851 is a wasteful number, since it uses less digits than its factorization.

212920831851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31261 (or 31241 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 42.

The spelling of 212920831851 in words is "two hundred twelve billion, nine hundred twenty million, eight hundred thirty-one thousand, eight hundred fifty-one".