1021249900 has 36 divisors (see below), whose sum is σ = 2417579640. Its totient is φ = 371363200.

The previous prime is 1021249883. The next prime is 1021249927. The reversal of 1021249900 is 99421201.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 463105 + ... + 465304.

It is an arithmetic number, because the mean of its divisors is an integer number (67154990).

Almost surely, 2^1021249900 is an apocalyptic number.

1021249900 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021249900 is an abundant number, since it is smaller than the sum of its proper divisors (1396329740).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1021249900 is a wasteful number, since it uses less digits than its factorization.

1021249900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 928434 (or 928427 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 1021249900 is about 31957.0007979472. Note that the first 3 decimals coincide. The cubic root of 1021249900 is about 1007.0337109176.

The spelling of 1021249900 in words is "one billion, twenty-one million, two hundred forty-nine thousand, nine hundred".