920988217 has 4 divisors (see below), whose sum is σ = 921060900. Its totient is φ = 920915536.

The previous prime is 920988193. The next prime is 920988223. The reversal of 920988217 is 712889029.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 64899136 + 856089081 = 8056^2 + 29259^2 .

It is a cyclic number.

It is not a de Polignac number, because 920988217 - 2¹⁵ = 920955449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (920982217) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11818 + ... + 44515.

It is an arithmetic number, because the mean of its divisors is an integer number (230265225).

Almost surely, 2^920988217 is an apocalyptic number.

It is an amenable number.

920988217 is a deficient number, since it is larger than the sum of its proper divisors (72683).

920988217 is a wasteful number, since it uses less digits than its factorization.

920988217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72682.

The product of its (nonzero) digits is 145152, while the sum is 46.

The square root of 920988217 is about 30347.7876788408. The cubic root of 920988217 is about 972.9369366846.

The spelling of 920988217 in words is "nine hundred twenty million, nine hundred eighty-eight thousand, two hundred seventeen".