1621623257029 has 4 divisors (see below), whose sum is σ = 1621661690880. Its totient is φ = 1621584823180.

The previous prime is 1621623256997. The next prime is 1621623257039. The reversal of 1621623257029 is 9207523261261.

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.

It is a cyclic number.

It is not a de Polignac number, because 1621623257029 - 2⁵ = 1621623256997 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1621623257029.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621623257039) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19153567 + ... + 19238044.

It is an arithmetic number, because the mean of its divisors is an integer number (405415422720).

Almost surely, 2^{1621623257029} is an apocalyptic number.

It is an amenable number.

1621623257029 is a deficient number, since it is larger than the sum of its proper divisors (38433851).

1621623257029 is an equidigital number, since it uses as much as digits as its factorization.

1621623257029 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38433850.

The product of its (nonzero) digits is 544320, while the sum is 46.

The spelling of 1621623257029 in words is "one trillion, six hundred twenty-one billion, six hundred twenty-three million, two hundred fifty-seven thousand, twenty-nine".