815206375249 has 6 divisors (see below), whose sum is σ = 948301293714. Its totient is φ = 698748321600.

The previous prime is 815206375237. The next prime is 815206375273. The reversal of 815206375249 is 942573602518.

It can be written as a sum of positive squares in only one way, i.e., 528446125249 + 286760250000 = 726943^2 + 535500^2 .

It is not a de Polignac number, because 815206375249 - 2¹⁹ = 815205850961 is a prime.

It is a super-2 number, since 2×815206375249² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 815206375196 and 815206375205.

It is not an unprimeable number, because it can be changed into a prime (815206375549) 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, 8318432352 + ... + 8318432449.

It is an arithmetic number, because the mean of its divisors is an integer number (158050215619).

It is a 2-persistent number, because it is pandigital, and so is 2⋅815206375249 = 1630412750498, but 3⋅815206375249 = 2445619125747 is not.

Almost surely, 2^815206375249 is an apocalyptic number.

It is an amenable number.

815206375249 is a deficient number, since it is larger than the sum of its proper divisors (133094918465).

815206375249 is a wasteful number, since it uses less digits than its factorization.

815206375249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16636864815 (or 16636864808 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 52.

The spelling of 815206375249 in words is "eight hundred fifteen billion, two hundred six million, three hundred seventy-five thousand, two hundred forty-nine".