1626456421021 has 4 divisors (see below), whose sum is σ = 1642559950044. Its totient is φ = 1610352892000.

The previous prime is 1626456421019. The next prime is 1626456421039. The reversal of 1626456421021 is 1201246546261.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 979533801796 + 646922619225 = 989714^2 + 804315^2 .

It is a cyclic number.

It is not a de Polignac number, because 1626456421021 - 2¹ = 1626456421019 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1626456121021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8051764360 + ... + 8051764561.

It is an arithmetic number, because the mean of its divisors is an integer number (410639987511).

Almost surely, 2^{1626456421021} is an apocalyptic number.

It is an amenable number.

1626456421021 is a deficient number, since it is larger than the sum of its proper divisors (16103529023).

1626456421021 is a wasteful number, since it uses less digits than its factorization.

1626456421021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16103529022.

The product of its (nonzero) digits is 138240, while the sum is 40.

The spelling of 1626456421021 in words is "one trillion, six hundred twenty-six billion, four hundred fifty-six million, four hundred twenty-one thousand, twenty-one".