80656819 has 2 divisors, whose sum is σ = 80656820. Its totient is φ = 80656818.

The previous prime is 80656769. The next prime is 80656847. The reversal of 80656819 is 91865608.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 80656819 - 2¹⁵ = 80624051 is a prime.

It is a super-2 number, since 2×80656819² = 13011044902397522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (80656019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40328409 + 40328410.

It is an arithmetic number, because the mean of its divisors is an integer number (40328410).

Almost surely, 2^80656819 is an apocalyptic number.

80656819 is a deficient number, since it is larger than the sum of its proper divisors (1).

80656819 is an equidigital number, since it uses as much as digits as its factorization.

80656819 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 103680, while the sum is 43.

The square root of 80656819 is about 8980.9141516886. The cubic root of 80656819 is about 432.0629534314.

It can be divided in two parts, 8065 and 6819, that added together give a square (14884 = 122²).

The spelling of 80656819 in words is "eighty million, six hundred fifty-six thousand, eight hundred nineteen".