1587651661 has 8 divisors (see below), whose sum is σ = 1665532800. Its totient is φ = 1511312880.

The previous prime is 1587651649. The next prime is 1587651673. The reversal of 1587651661 is 1661567851.

It is an interprime number because it is at equal distance from previous prime (1587651649) and next prime (1587651673).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1587651661 - 2¹⁷ = 1587520589 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 (1587651161) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 383481 + ... + 387598.

It is an arithmetic number, because the mean of its divisors is an integer number (208191600).

Almost surely, 2^1587651661 is an apocalyptic number.

It is an amenable number.

1587651661 is a deficient number, since it is larger than the sum of its proper divisors (77881139).

1587651661 is an equidigital number, since it uses as much as digits as its factorization.

1587651661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 771179.

The product of its digits is 302400, while the sum is 46.

The square root of 1587651661 is about 39845.3467923169. The cubic root of 1587651661 is about 1166.5904244689.

The spelling of 1587651661 in words is "one billion, five hundred eighty-seven million, six hundred fifty-one thousand, six hundred sixty-one".