1355456621 has 4 divisors (see below), whose sum is σ = 1386978912. Its totient is φ = 1323934332.

The previous prime is 1355456611. The next prime is 1355456623. The reversal of 1355456621 is 1266545531.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1266545531 = 23 ⋅55067197.

It is a cyclic number.

It is not a de Polignac number, because 1355456621 - 2¹⁰ = 1355455597 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 (1355456623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15761081 + ... + 15761166.

It is an arithmetic number, because the mean of its divisors is an integer number (346744728).

Almost surely, 2^1355456621 is an apocalyptic number.

It is an amenable number.

1355456621 is a deficient number, since it is larger than the sum of its proper divisors (31522291).

1355456621 is an equidigital number, since it uses as much as digits as its factorization.

1355456621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31522290.

The product of its digits is 108000, while the sum is 38.

The square root of 1355456621 is about 36816.5264657056. The cubic root of 1355456621 is about 1106.6965118219.

The spelling of 1355456621 in words is "one billion, three hundred fifty-five million, four hundred fifty-six thousand, six hundred twenty-one".