1621455345 has 48 divisors (see below), whose sum is σ = 2974233600. Its totient is φ = 814890240.

The previous prime is 1621455343. The next prime is 1621455347. The reversal of 1621455345 is 5435541261.

1621455345 is a `hidden beast` number, since 1 + 62 + 1 + 4 + 553 + 45 = 666.

It is an interprime number because it is at equal distance from previous prime (1621455343) and next prime (1621455347).

It is not a de Polignac number, because 1621455345 - 2¹ = 1621455343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1621455343) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 158341 + ... + 168269.

It is an arithmetic number, because the mean of its divisors is an integer number (61963200).

Almost surely, 2^1621455345 is an apocalyptic number.

1621455345 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1621455345 is a deficient number, since it is larger than the sum of its proper divisors (1352778255).

1621455345 is a wasteful number, since it uses less digits than its factorization.

1621455345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10150 (or 10147 counting only the distinct ones).

The product of its digits is 72000, while the sum is 36.

The square root of 1621455345 is about 40267.2987050286. The cubic root of 1621455345 is about 1174.8118835708.

The spelling of 1621455345 in words is "one billion, six hundred twenty-one million, four hundred fifty-five thousand, three hundred forty-five".