1221353393 has 8 divisors (see below), whose sum is σ = 1327372200. Its totient is φ = 1117058688.

The previous prime is 1221353317. The next prime is 1221353401. The reversal of 1221353393 is 3933531221.

It can be written as a sum of positive squares in 4 ways, for example, as 370639504 + 850713889 = 19252^2 + 29167^2 .

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 1221353393 - 2⁸ = 1221353137 is a prime.

It is a super-2 number, since 2×1221353393² = 2983408221185224898, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1221353303) 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, 429548 + ... + 432381.

It is an arithmetic number, because the mean of its divisors is an integer number (165921525).

Almost surely, 2^1221353393 is an apocalyptic number.

1221353393 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1221353393 is a deficient number, since it is larger than the sum of its proper divisors (106018807).

1221353393 is a wasteful number, since it uses less digits than its factorization.

1221353393 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 862051.

The product of its digits is 14580, while the sum is 32.

The square root of 1221353393 is about 34947.8667875451. The cubic root of 1221353393 is about 1068.9247045295.

The spelling of 1221353393 in words is "one billion, two hundred twenty-one million, three hundred fifty-three thousand, three hundred ninety-three".