217977408627364 has 27 divisors (see below), whose sum is σ = 405220181568643. Its totient is φ = 102577367835008.

The previous prime is 217977408627359. The next prime is 217977408627389. The reversal of 217977408627364 is 463726804779712.

The square root of 217977408627364 is 14764058.

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

It can be written as a sum of positive squares in 4 ways, for example, as 30095559627364 + 187881849000000 = 5485942^2 + 13707000^2 .

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 501760854 + ... + 502195090.

Almost surely, 2^{217977408627364} is an apocalyptic number.

217977408627364 is the 14764058-th square number.

It is an amenable number.

217977408627364 is a deficient number, since it is larger than the sum of its proper divisors (187242772941279).

217977408627364 is an frugal number, since it uses more digits than its factorization.

217977408627364 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 868512 (or 434256 counting only the distinct ones).

The product of its (nonzero) digits is 1194891264, while the sum is 73.

The spelling of 217977408627364 in words is "two hundred seventeen trillion, nine hundred seventy-seven billion, four hundred eight million, six hundred twenty-seven thousand, three hundred sixty-four".