217608936980 has 12 divisors (see below), whose sum is σ = 456978767700. Its totient is φ = 87043574784.

The previous prime is 217608936973. The next prime is 217608936989. The reversal of 217608936980 is 89639806712.

It can be written as a sum of positive squares in 2 ways, for example, as 171160928656 + 46448008324 = 413716^2 + 215518^2 .

It is a super-2 number, since 2×217608936980² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (59) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217608936989) 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, 5440223405 + ... + 5440223444.

It is an arithmetic number, because the mean of its divisors is an integer number (38081563975).

Almost surely, 2^217608936980 is an apocalyptic number.

217608936980 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217608936980 is an abundant number, since it is smaller than the sum of its proper divisors (239369830720).

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

217608936980 is a wasteful number, since it uses less digits than its factorization.

217608936980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10880446858 (or 10880446856 counting only the distinct ones).

The product of its (nonzero) digits is 7838208, while the sum is 59.

The spelling of 217608936980 in words is "two hundred seventeen billion, six hundred eight million, nine hundred thirty-six thousand, nine hundred eighty".