1221762680 has 16 divisors (see below), whose sum is σ = 2748966120. Its totient is φ = 488705056.

The previous prime is 1221762679. The next prime is 1221762709. The reversal of 1221762680 is 862671221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221762680.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15271994 + ... + 15272073.

Almost surely, 2^1221762680 is an apocalyptic number.

1221762680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221762680 is an abundant number, since it is smaller than the sum of its proper divisors (1527203440).

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

1221762680 is a wasteful number, since it uses less digits than its factorization.

1221762680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30544078 (or 30544074 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 35.

The square root of 1221762680 is about 34953.7219763504. The cubic root of 1221762680 is about 1069.0440934324.

The spelling of 1221762680 in words is "one billion, two hundred twenty-one million, seven hundred sixty-two thousand, six hundred eighty".