212915487978 has 16 divisors (see below), whose sum is σ = 473145528960. Its totient is φ = 70971829308.

The previous prime is 212915487949. The next prime is 212915488021. The reversal of 212915487978 is 879784519212.

212915487978 is a `hidden beast` number, since 2 + 12 + 9 + 1 + 548 + 7 + 9 + 78 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1971439650 + ... + 1971439757.

It is an arithmetic number, because the mean of its divisors is an integer number (29571595560).

Almost surely, 2^212915487978 is an apocalyptic number.

212915487978 is an abundant number, since it is smaller than the sum of its proper divisors (260230040982).

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

212915487978 is a wasteful number, since it uses less digits than its factorization.

212915487978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3942879418 (or 3942879412 counting only the distinct ones).

The product of its digits is 20321280, while the sum is 63.

The spelling of 212915487978 in words is "two hundred twelve billion, nine hundred fifteen million, four hundred eighty-seven thousand, nine hundred seventy-eight".