81026129 has 2 divisors, whose sum is σ = 81026130. Its totient is φ = 81026128.

The previous prime is 81026059. The next prime is 81026149. The reversal of 81026129 is 92162018.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 78287104 + 2739025 = 8848^2 + 1655^2 .

It is a cyclic number.

It is not a de Polignac number, because 81026129 - 2¹² = 81022033 is a prime.

It is not a weakly prime, because it can be changed into another prime (81026149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40513064 + 40513065.

It is an arithmetic number, because the mean of its divisors is an integer number (40513065).

Almost surely, 2^81026129 is an apocalyptic number.

It is an amenable number.

81026129 is a deficient number, since it is larger than the sum of its proper divisors (1).

81026129 is an equidigital number, since it uses as much as digits as its factorization.

81026129 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 29.

The square root of 81026129 is about 9001.4514940647. The cubic root of 81026129 is about 432.7213902128.

The spelling of 81026129 in words is "eighty-one million, twenty-six thousand, one hundred twenty-nine".