88139561 has 2 divisors, whose sum is σ = 88139562. Its totient is φ = 88139560.

The previous prime is 88139549. The next prime is 88139567. The reversal of 88139561 is 16593188.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74926336 + 13213225 = 8656^2 + 3635^2 .

It is a cyclic number.

It is not a de Polignac number, because 88139561 - 2¹⁰ = 88138537 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (88139567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 44069780 + 44069781.

It is an arithmetic number, because the mean of its divisors is an integer number (44069781).

Almost surely, 2^88139561 is an apocalyptic number.

It is an amenable number.

88139561 is a deficient number, since it is larger than the sum of its proper divisors (1).

88139561 is an equidigital number, since it uses as much as digits as its factorization.

88139561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 51840, while the sum is 41.

The square root of 88139561 is about 9388.2671990096. The cubic root of 88139561 is about 445.0310309548.

The spelling of 88139561 in words is "eighty-eight million, one hundred thirty-nine thousand, five hundred sixty-one".