1221757436 has 24 divisors (see below), whose sum is σ = 2167945920. Its totient is φ = 602364672.

The previous prime is 1221757429. The next prime is 1221757457. The reversal of 1221757436 is 6347571221.

It is a self number, because there is not a number n which added to its sum of digits gives 1221757436.

It is a congruent number.

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, 299120 + ... + 303176.

It is an arithmetic number, because the mean of its divisors is an integer number (90331080).

Almost surely, 2^1221757436 is an apocalyptic number.

It is an amenable number.

1221757436 is a deficient number, since it is larger than the sum of its proper divisors (946188484).

1221757436 is a wasteful number, since it uses less digits than its factorization.

1221757436 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5093 (or 5091 counting only the distinct ones).

The product of its digits is 70560, while the sum is 38.

The square root of 1221757436 is about 34953.6469627992. The cubic root of 1221757436 is about 1069.0425639277.

The spelling of 1221757436 in words is "one billion, two hundred twenty-one million, seven hundred fifty-seven thousand, four hundred thirty-six".