1621447645450 has 48 divisors (see below), whose sum is σ = 3045788628480. Its totient is φ = 642152358720.

The previous prime is 1621447645409. The next prime is 1621447645457. The reversal of 1621447645450 is 545467441261.

It is a junction number, because it is equal to n+sod(n) for n = 1621447645394 and 1621447645403.

It is not an unprimeable number, because it can be changed into a prime (1621447645457) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 27816936 + ... + 27875164.

It is an arithmetic number, because the mean of its divisors is an integer number (63453929760).

Almost surely, 2^{1621447645450} is an apocalyptic number.

1621447645450 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1621447645450 is a deficient number, since it is larger than the sum of its proper divisors (1424340983030).

1621447645450 is a wasteful number, since it uses less digits than its factorization.

1621447645450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63751 (or 63746 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 49.

The spelling of 1621447645450 in words is "one trillion, six hundred twenty-one billion, four hundred forty-seven million, six hundred forty-five thousand, four hundred fifty".