1021023139 has 4 divisors (see below), whose sum is σ = 1030058856. Its totient is φ = 1011987424.

The previous prime is 1021023131. The next prime is 1021023149. The reversal of 1021023139 is 9313201201.

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

It is a cyclic number.

It is not a de Polignac number, because 1021023139 - 2³ = 1021023131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1021023131) 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, 4517689 + ... + 4517914.

It is an arithmetic number, because the mean of its divisors is an integer number (257514714).

Almost surely, 2^1021023139 is an apocalyptic number.

1021023139 is a deficient number, since it is larger than the sum of its proper divisors (9035717).

1021023139 is an equidigital number, since it uses as much as digits as its factorization.

1021023139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9035716.

The product of its (nonzero) digits is 324, while the sum is 22.

The square root of 1021023139 is about 31953.4526929407. The cubic root of 1021023139 is about 1006.9591706002.

The spelling of 1021023139 in words is "one billion, twenty-one million, twenty-three thousand, one hundred thirty-nine".