1021211440 has 20 divisors (see below), whose sum is σ = 2374316784. Its totient is φ = 408484544.

The previous prime is 1021211419. The next prime is 1021211453. The reversal of 1021211440 is 441121201.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (16).

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 3 ways as a sum of consecutive naturals, for example, 6382492 + ... + 6382651.

Almost surely, 2^1021211440 is an apocalyptic number.

1021211440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021211440 is an abundant number, since it is smaller than the sum of its proper divisors (1353105344).

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

1021211440 is a wasteful number, since it uses less digits than its factorization.

1021211440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12765156 (or 12765150 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 1021211440 is about 31956.3990462004. The cubic root of 1021211440 is about 1007.0210692182.

Adding to 1021211440 its reverse (441121201), we get a palindrome (1462332641).

The spelling of 1021211440 in words is "one billion, twenty-one million, two hundred eleven thousand, four hundred forty".