1631387 has 4 divisors (see below), whose sum is σ = 1641936. Its totient is φ = 1620840.

The previous prime is 1631369. The next prime is 1631407. The reversal of 1631387 is 7831361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7831361 = 193 ⋅40577.

It is a cyclic number.

It is not a de Polignac number, because 1631387 - 2¹⁸ = 1369243 is a prime.

It is a super-2 number, since 2×1631387² = 5322847087538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1639387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5039 + ... + 5352.

It is an arithmetic number, because the mean of its divisors is an integer number (410484).

2^1631387 is an apocalyptic number.

1631387 is a deficient number, since it is larger than the sum of its proper divisors (10549).

1631387 is a wasteful number, since it uses less digits than its factorization.

1631387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10548.

The product of its digits is 3024, while the sum is 29.

The square root of 1631387 is about 1277.2576090985. The cubic root of 1631387 is about 117.7205635311.

The spelling of 1631387 in words is "one million, six hundred thirty-one thousand, three hundred eighty-seven".