8121490905 has 16 divisors (see below), whose sum is σ = 14175693504. Its totient is φ = 3937692480.

The previous prime is 8121490889. The next prime is 8121490921. The reversal of 8121490905 is 5090941218.

It is an interprime number because it is at equal distance from previous prime (8121490889) and next prime (8121490921).

It is not a de Polignac number, because 8121490905 - 2⁴ = 8121490889 is a prime.

It is a super-2 number, since 2×8121490905² (a number of 21 digits) contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24610414 + ... + 24610743.

It is an arithmetic number, because the mean of its divisors is an integer number (885980844).

Almost surely, 2^8121490905 is an apocalyptic number.

It is an amenable number.

8121490905 is a deficient number, since it is larger than the sum of its proper divisors (6054202599).

8121490905 is a wasteful number, since it uses less digits than its factorization.

8121490905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49221176.

The product of its (nonzero) digits is 25920, while the sum is 39.

The square root of 8121490905 is about 90119.3148276217. The cubic root of 8121490905 is about 2010.0734200057.

The spelling of 8121490905 in words is "eight billion, one hundred twenty-one million, four hundred ninety thousand, nine hundred five".