1217605920 has 48 divisors (see below), whose sum is σ = 3835460160. Its totient is φ = 324694784.

The previous prime is 1217605903. The next prime is 1217605957. The reversal of 1217605920 is 295067121.

It is a tau number, because it is divible by the number of its divisors (48).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1267860 + ... + 1268819.

It is an arithmetic number, because the mean of its divisors is an integer number (79905420).

Almost surely, 2^1217605920 is an apocalyptic number.

1217605920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1217605920 is an abundant number, since it is smaller than the sum of its proper divisors (2617854240).

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

1217605920 is a wasteful number, since it uses less digits than its factorization.

1217605920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2536697 (or 2536689 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 1217605920 is about 34894.2104080319. The cubic root of 1217605920 is about 1067.8303255538.

The spelling of 1217605920 in words is "one billion, two hundred seventeen million, six hundred five thousand, nine hundred twenty".