88123781 has 4 divisors (see below), whose sum is σ = 88402092. Its totient is φ = 87845472.

The previous prime is 88123769. The next prime is 88123799. The reversal of 88123781 is 18732188.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2265025 + 85858756 = 1505^2 + 9266^2 .

It is a cyclic number.

It is not a de Polignac number, because 88123781 - 2¹⁸ = 87861637 is a prime.

It is a super-2 number, since 2×88123781² = 15531601555471922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (88123181) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 138680 + ... + 139313.

It is an arithmetic number, because the mean of its divisors is an integer number (22100523).

Almost surely, 2^88123781 is an apocalyptic number.

It is an amenable number.

88123781 is a deficient number, since it is larger than the sum of its proper divisors (278311).

88123781 is a wasteful number, since it uses less digits than its factorization.

88123781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 278310.

The product of its digits is 21504, while the sum is 38.

The square root of 88123781 is about 9387.4267507129. The cubic root of 88123781 is about 445.0044707711.

The spelling of 88123781 in words is "eighty-eight million, one hundred twenty-three thousand, seven hundred eighty-one".