1605428087 has 4 divisors (see below), whose sum is σ = 1612438920. Its totient is φ = 1598417256.

The previous prime is 1605428059. The next prime is 1605428089. The reversal of 1605428087 is 7808245061.

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 1605428087 - 2¹⁸ = 1605165943 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1605428089) 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, 3505073 + ... + 3505530.

It is an arithmetic number, because the mean of its divisors is an integer number (403109730).

Almost surely, 2^1605428087 is an apocalyptic number.

1605428087 is a deficient number, since it is larger than the sum of its proper divisors (7010833).

1605428087 is an equidigital number, since it uses as much as digits as its factorization.

1605428087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7010832.

The product of its (nonzero) digits is 107520, while the sum is 41.

The square root of 1605428087 is about 40067.7936377835. The cubic root of 1605428087 is about 1170.9282542644.

The spelling of 1605428087 in words is "one billion, six hundred five million, four hundred twenty-eight thousand, eighty-seven".