81626970587 has 2 divisors, whose sum is σ = 81626970588. Its totient is φ = 81626970586.

The previous prime is 81626970541. The next prime is 81626970611. The reversal of 81626970587 is 78507962618.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81626970587 - 2¹⁶ = 81626905051 is a prime.

It is not a weakly prime, because it can be changed into another prime (81626970487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40813485293 + 40813485294.

It is an arithmetic number, because the mean of its divisors is an integer number (40813485294).

Almost surely, 2^81626970587 is an apocalyptic number.

81626970587 is a deficient number, since it is larger than the sum of its proper divisors (1).

81626970587 is an equidigital number, since it uses as much as digits as its factorization.

81626970587 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10160640, while the sum is 59.

The spelling of 81626970587 in words is "eighty-one billion, six hundred twenty-six million, nine hundred seventy thousand, five hundred eighty-seven".