79454021 has 2 divisors, whose sum is σ = 79454022. Its totient is φ = 79454020.

The previous prime is 79454009. The next prime is 79454033. The reversal of 79454021 is 12045497.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (79454009) and next prime (79454033).

It can be written as a sum of positive squares in only one way, i.e., 53085796 + 26368225 = 7286^2 + 5135^2 .

It is an emirp because it is prime and its reverse (12045497) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-79454021 is a prime.

It is equal to p_4639433 and since 79454021 and 4639433 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (79454051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39727010 + 39727011.

It is an arithmetic number, because the mean of its divisors is an integer number (39727011).

Almost surely, 2^79454021 is an apocalyptic number.

It is an amenable number.

79454021 is a deficient number, since it is larger than the sum of its proper divisors (1).

79454021 is an equidigital number, since it uses as much as digits as its factorization.

79454021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 79454021 is about 8913.6985028662. The cubic root of 79454021 is about 429.9044694938.

The spelling of 79454021 in words is "seventy-nine million, four hundred fifty-four thousand, twenty-one".