1221158064 has 80 divisors (see below), whose sum is σ = 3702802688. Its totient is φ = 339469056.

The previous prime is 1221158047. The next prime is 1221158083. The reversal of 1221158064 is 4608511221.

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, 36682 + ... + 61545.

Almost surely, 2^1221158064 is an apocalyptic number.

1221158064 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

1221158064 is an abundant number, since it is smaller than the sum of its proper divisors (2481644624).

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

1221158064 is a wasteful number, since it uses less digits than its factorization.

1221158064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98282 (or 98276 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 1221158064 is about 34945.0720989384. The cubic root of 1221158064 is about 1068.8677177130.

Adding to 1221158064 its reverse (4608511221), we get a palindrome (5829669285).

The spelling of 1221158064 in words is "one billion, two hundred twenty-one million, one hundred fifty-eight thousand, sixty-four".