721966138212 has 48 divisors (see below), whose sum is σ = 1837782100224. Its totient is φ = 218771652000.

The previous prime is 721966138207. The next prime is 721966138217. The reversal of 721966138212 is 212831669127.

It is an interprime number because it is at equal distance from previous prime (721966138207) and next prime (721966138217).

It is not an unprimeable number, because it can be changed into a prime (721966138217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8539387 + ... + 8623517.

It is an arithmetic number, because the mean of its divisors is an integer number (38287127088).

Almost surely, 2^721966138212 is an apocalyptic number.

It is an amenable number.

721966138212 is an abundant number, since it is smaller than the sum of its proper divisors (1115815962012).

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

721966138212 is a wasteful number, since it uses less digits than its factorization.

721966138212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149160 (or 149158 counting only the distinct ones).

The product of its digits is 435456, while the sum is 48.

The spelling of 721966138212 in words is "seven hundred twenty-one billion, nine hundred sixty-six million, one hundred thirty-eight thousand, two hundred twelve".