1221757901 has 8 divisors (see below), whose sum is σ = 1503702144. Its totient is φ = 966665520.

The previous prime is 1221757897. The next prime is 1221757909. The reversal of 1221757901 is 1097571221.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1221757901 - 2² = 1221757897 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221757909) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6712865 + ... + 6713046.

It is an arithmetic number, because the mean of its divisors is an integer number (187962768).

Almost surely, 2^1221757901 is an apocalyptic number.

It is an amenable number.

1221757901 is a deficient number, since it is larger than the sum of its proper divisors (281944243).

1221757901 is a wasteful number, since it uses less digits than its factorization.

1221757901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13425931.

The product of its (nonzero) digits is 8820, while the sum is 35.

The square root of 1221757901 is about 34953.6536144650. The cubic root of 1221757901 is about 1069.0426995533.

The spelling of 1221757901 in words is "one billion, two hundred twenty-one million, seven hundred fifty-seven thousand, nine hundred one".