1021313638 has 4 divisors (see below), whose sum is σ = 1531970460. Its totient is φ = 510656818.

The previous prime is 1021313617. The next prime is 1021313663. The reversal of 1021313638 is 8363131201.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255328408 + ... + 255328411.

It is an arithmetic number, because the mean of its divisors is an integer number (382992615).

Almost surely, 2^1021313638 is an apocalyptic number.

1021313638 is a deficient number, since it is larger than the sum of its proper divisors (510656822).

1021313638 is an equidigital number, since it uses as much as digits as its factorization.

1021313638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510656821.

The product of its (nonzero) digits is 2592, while the sum is 28.

The square root of 1021313638 is about 31957.9980286626. The cubic root of 1021313638 is about 1007.0546607293.

Adding to 1021313638 its reverse (8363131201), we get a palindrome (9384444839).

The spelling of 1021313638 in words is "one billion, twenty-one million, three hundred thirteen thousand, six hundred thirty-eight".