1621726079 has 4 divisors (see below), whose sum is σ = 1622040984. Its totient is φ = 1621411176.

The previous prime is 1621726069. The next prime is 1621726103. The reversal of 1621726079 is 9706271261.

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

It is a cyclic number.

It is not a de Polignac number, because 1621726079 - 2⁴ = 1621726063 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1621726069) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 149597 + ... + 160070.

It is an arithmetic number, because the mean of its divisors is an integer number (405510246).

Almost surely, 2^1621726079 is an apocalyptic number.

1621726079 is a deficient number, since it is larger than the sum of its proper divisors (314905).

1621726079 is an equidigital number, since it uses as much as digits as its factorization.

1621726079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314904.

The product of its (nonzero) digits is 63504, while the sum is 41.

The square root of 1621726079 is about 40270.6602751929. The cubic root of 1621726079 is about 1174.8772659490.

The spelling of 1621726079 in words is "one billion, six hundred twenty-one million, seven hundred twenty-six thousand, seventy-nine".