1021399108 has 12 divisors (see below), whose sum is σ = 1791034000. Its totient is φ = 509675112.

The previous prime is 1021399103. The next prime is 1021399153. The reversal of 1021399108 is 8019931201.

It is a super-2 number, since 2×1021399108² = 2086512275646391328, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1021399103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 253866 + ... + 257857.

Almost surely, 2^1021399108 is an apocalyptic number.

It is an amenable number.

1021399108 is a deficient number, since it is larger than the sum of its proper divisors (769634892).

1021399108 is a wasteful number, since it uses less digits than its factorization.

1021399108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 512226 (or 512224 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 1021399108 is about 31959.3352246257. The cubic root of 1021399108 is about 1007.0827521852.

The spelling of 1021399108 in words is "one billion, twenty-one million, three hundred ninety-nine thousand, one hundred eight".