212215927561 has 9 divisors (see below), whose sum is σ = 233267705293. Its totient is φ = 192918963820.

The previous prime is 212215927543. The next prime is 212215927571. The reversal of 212215927561 is 165729512212.

The square root of 212215927561 is 460669.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 212215927561 - 2²⁹ = 211679056649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (212215927541) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5046420 + ... + 5088298.

Almost surely, 2^212215927561 is an apocalyptic number.

212215927561 is the 460669-th square number.

212215927561 is the 230335-th centered octagonal number.

It is an amenable number.

212215927561 is a deficient number, since it is larger than the sum of its proper divisors (21051777732).

212215927561 is an frugal number, since it uses more digits than its factorization.

212215927561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83780 (or 41890 counting only the distinct ones).

The product of its digits is 151200, while the sum is 43.

The spelling of 212215927561 in words is "two hundred twelve billion, two hundred fifteen million, nine hundred twenty-seven thousand, five hundred sixty-one".