1221780620258 has 24 divisors (see below), whose sum is σ = 2017338924720. Its totient is φ = 554551054200.

The previous prime is 1221780620227. The next prime is 1221780620297. The reversal of 1221780620258 is 8520260871221.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3485948 + ... + 3820391.

It is an arithmetic number, because the mean of its divisors is an integer number (84055788530).

Almost surely, 2^{1221780620258} is an apocalyptic number.

1221780620258 is a deficient number, since it is larger than the sum of its proper divisors (795558304462).

1221780620258 is a wasteful number, since it uses less digits than its factorization.

1221780620258 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7307054 (or 7307043 counting only the distinct ones).

The product of its (nonzero) digits is 215040, while the sum is 44.

The spelling of 1221780620258 in words is "one trillion, two hundred twenty-one billion, seven hundred eighty million, six hundred twenty thousand, two hundred fifty-eight".