1621255363 has 12 divisors (see below), whose sum is σ = 2006356368. Its totient is φ = 1282750560.

The previous prime is 1621255357. The next prime is 1621255369. The reversal of 1621255363 is 3635521261.

It is an interprime number because it is at equal distance from previous prime (1621255357) and next prime (1621255369).

It is not a de Polignac number, because 1621255363 - 2¹⁷ = 1621124291 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1621255369) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 684048 + ... + 686413.

It is an arithmetic number, because the mean of its divisors is an integer number (167196364).

Almost surely, 2^1621255363 is an apocalyptic number.

1621255363 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1621255363 is a deficient number, since it is larger than the sum of its proper divisors (385101005).

1621255363 is a wasteful number, since it uses less digits than its factorization.

1621255363 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1370494 (or 1370481 counting only the distinct ones).

The product of its digits is 32400, while the sum is 34.

The square root of 1621255363 is about 40264.8154472363. The cubic root of 1621255363 is about 1174.7635831575.

The spelling of 1621255363 in words is "one billion, six hundred twenty-one million, two hundred fifty-five thousand, three hundred sixty-three".