1217921210 has 32 divisors (see below), whose sum is σ = 2397605184. Its totient is φ = 441760000.

The previous prime is 1217921179. The next prime is 1217921249. The reversal of 1217921210 is 121297121.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1217921210.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30305 + ... + 57915.

It is an arithmetic number, because the mean of its divisors is an integer number (74925162).

Almost surely, 2^1217921210 is an apocalyptic number.

1217921210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1217921210 is a deficient number, since it is larger than the sum of its proper divisors (1179683974).

1217921210 is a wasteful number, since it uses less digits than its factorization.

1217921210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28030.

The product of its (nonzero) digits is 504, while the sum is 26.

The square root of 1217921210 is about 34898.7279137793. The cubic root of 1217921210 is about 1067.9224865073.

The spelling of 1217921210 in words is "one billion, two hundred seventeen million, nine hundred twenty-one thousand, two hundred ten".