1221385759 has 8 divisors (see below), whose sum is σ = 1402548480. Its totient is φ = 1051911000.

The previous prime is 1221385747. The next prime is 1221385769. The reversal of 1221385759 is 9575831221.

It is a happy number.

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 1221385759 - 2¹⁵ = 1221352991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221385769) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2921767 + ... + 2922184.

It is an arithmetic number, because the mean of its divisors is an integer number (175318560).

Almost surely, 2^1221385759 is an apocalyptic number.

1221385759 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

1221385759 is a deficient number, since it is larger than the sum of its proper divisors (181162721).

1221385759 is a wasteful number, since it uses less digits than its factorization.

1221385759 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5843981.

The product of its digits is 151200, while the sum is 43.

The square root of 1221385759 is about 34948.3298456450. The cubic root of 1221385759 is about 1068.9341466538.

The spelling of 1221385759 in words is "one billion, two hundred twenty-one million, three hundred eighty-five thousand, seven hundred fifty-nine".