102280405 has 4 divisors (see below), whose sum is σ = 122736492. Its totient is φ = 81824320.

The previous prime is 102280403. The next prime is 102280411. The reversal of 102280405 is 504082201.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 504082201 = 7 ⋅72011743.

It can be written as a sum of positive squares in 2 ways, for example, as 62110161 + 40170244 = 7881^2 + 6338^2 .

It is not a de Polignac number, because 102280405 - 2¹ = 102280403 is a prime.

It is a super-2 number, since 2×102280405² = 20922562493928050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (102280403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10228036 + ... + 10228045.

It is an arithmetic number, because the mean of its divisors is an integer number (30684123).

Almost surely, 2^102280405 is an apocalyptic number.

It is an amenable number.

102280405 is a deficient number, since it is larger than the sum of its proper divisors (20456087).

102280405 is an equidigital number, since it uses as much as digits as its factorization.

102280405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20456086.

The product of its (nonzero) digits is 640, while the sum is 22.

The square root of 102280405 is about 10113.3775268206. The cubic root of 102280405 is about 467.6606328383.

The spelling of 102280405 in words is "one hundred two million, two hundred eighty thousand, four hundred five".