1021404440 has 32 divisors (see below), whose sum is σ = 2626469280. Its totient is φ = 350195712.

The previous prime is 1021404437. The next prime is 1021404457. The reversal of 1021404440 is 444041201.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1823657 + ... + 1824216.

It is an arithmetic number, because the mean of its divisors is an integer number (82077165).

Almost surely, 2^1021404440 is an apocalyptic number.

1021404440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021404440 is an abundant number, since it is smaller than the sum of its proper divisors (1605064840).

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

1021404440 is a wasteful number, since it uses less digits than its factorization.

1021404440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3647891 (or 3647887 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 20.

The square root of 1021404440 is about 31959.4186430229. The cubic root of 1021404440 is about 1007.0845046036.

Adding to 1021404440 its reverse (444041201), we get a palindrome (1465445641).

The spelling of 1021404440 in words is "one billion, twenty-one million, four hundred four thousand, four hundred forty".