79543621 has 2 divisors, whose sum is σ = 79543622. Its totient is φ = 79543620.

The previous prime is 79543609. The next prime is 79543627. The reversal of 79543621 is 12634597.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65772100 + 13771521 = 8110^2 + 3711^2 .

It is an emirp because it is prime and its reverse (12634597) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 79543621 - 2¹¹ = 79541573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79543627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39771810 + 39771811.

It is an arithmetic number, because the mean of its divisors is an integer number (39771811).

Almost surely, 2^79543621 is an apocalyptic number.

It is an amenable number.

79543621 is a deficient number, since it is larger than the sum of its proper divisors (1).

79543621 is an equidigital number, since it uses as much as digits as its factorization.

79543621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 45360, while the sum is 37.

The square root of 79543621 is about 8918.7230588241. The cubic root of 79543621 is about 430.0660093364.

The spelling of 79543621 in words is "seventy-nine million, five hundred forty-three thousand, six hundred twenty-one".