102813809 has 6 divisors (see below), whose sum is σ = 119599794. Its totient is φ = 88126080.

The previous prime is 102813803. The next prime is 102813811. The reversal of 102813809 is 908318201.

It can be written as a sum of positive squares in only one way, i.e., 80156209 + 22657600 = 8953^2 + 4760^2 .

It is not a de Polignac number, because 102813809 - 2⁴ = 102813793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (102813803) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1049072 + ... + 1049169.

It is an arithmetic number, because the mean of its divisors is an integer number (19933299).

Almost surely, 2^102813809 is an apocalyptic number.

It is an amenable number.

102813809 is a deficient number, since it is larger than the sum of its proper divisors (16785985).

102813809 is an equidigital number, since it uses as much as digits as its factorization.

102813809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2098255 (or 2098248 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 102813809 is about 10139.7144437109. The cubic root of 102813809 is about 468.4721915590.

The spelling of 102813809 in words is "one hundred two million, eight hundred thirteen thousand, eight hundred nine".