102981905 has 16 divisors (see below), whose sum is σ = 133790160. Its totient is φ = 75644928.

The previous prime is 102981899. The next prime is 102981911. The reversal of 102981905 is 509189201.

It is a Cunningham number, because it is equal to 10148²+1.

It is an interprime number because it is at equal distance from previous prime (102981899) and next prime (102981911).

It can be written as a sum of positive squares in 8 ways, for example, as 38837824 + 64144081 = 6232^2 + 8009^2 .

It is a cyclic number.

It is not a de Polignac number, because 102981905 - 2⁴ = 102981889 is a prime.

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, 8441 + ... + 16649.

It is an arithmetic number, because the mean of its divisors is an integer number (8361885).

Almost surely, 2^102981905 is an apocalyptic number.

It is an amenable number.

102981905 is a deficient number, since it is larger than the sum of its proper divisors (30808255).

102981905 is a wasteful number, since it uses less digits than its factorization.

102981905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8420.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 102981905 is about 10148.0000492708. Note that the first 4 decimals coincide. The cubic root of 102981905 is about 468.7273629364.

The spelling of 102981905 in words is "one hundred two million, nine hundred eighty-one thousand, nine hundred five".