1687403993 has 16 divisors (see below), whose sum is σ = 1928005632. Its totient is φ = 1461834000.

The previous prime is 1687403987. The next prime is 1687403999. The reversal of 1687403993 is 3993047861.

It is an interprime number because it is at equal distance from previous prime (1687403987) and next prime (1687403999).

It is not a de Polignac number, because 1687403993 - 2¹⁸ = 1687141849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1687403999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56258 + ... + 80868.

It is an arithmetic number, because the mean of its divisors is an integer number (120500352).

Almost surely, 2^1687403993 is an apocalyptic number.

It is an amenable number.

1687403993 is a deficient number, since it is larger than the sum of its proper divisors (240601639).

1687403993 is a wasteful number, since it uses less digits than its factorization.

1687403993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24916.

The product of its (nonzero) digits is 979776, while the sum is 50.

The square root of 1687403993 is about 41078.0232362756. The cubic root of 1687403993 is about 1190.5282105312.

The spelling of 1687403993 in words is "one billion, six hundred eighty-seven million, four hundred three thousand, nine hundred ninety-three".