1020139 has 4 divisors (see below), whose sum is σ = 1022256. Its totient is φ = 1018024.

The previous prime is 1020137. The next prime is 1020143. The reversal of 1020139 is 9310201.

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 1020139 - 2¹ = 1020137 is a prime.

It is a Duffinian number.

1020139 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (1020137) 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, 57 + ... + 1429.

It is an arithmetic number, because the mean of its divisors is an integer number (255564).

2^1020139 is an apocalyptic number.

1020139 is a deficient number, since it is larger than the sum of its proper divisors (2117).

1020139 is an equidigital number, since it uses as much as digits as its factorization.

1020139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2116.

The product of its (nonzero) digits is 54, while the sum is 16.

The square root of 1020139 is about 1010.0193067462. The cubic root of 1020139 is about 100.6668433155. Note that the first 3 decimals are identical.

The spelling of 1020139 in words is "one million, twenty thousand, one hundred thirty-nine".