1631649 has 4 divisors (see below), whose sum is σ = 2175536. Its totient is φ = 1087764.

The previous prime is 1631647. The next prime is 1631657. The reversal of 1631649 is 9461361.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1631649 - 2¹ = 1631647 is a prime.

It is a D-number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1631647) 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, 271939 + ... + 271944.

It is an arithmetic number, because the mean of its divisors is an integer number (543884).

2^1631649 is an apocalyptic number.

It is an amenable number.

1631649 is a deficient number, since it is larger than the sum of its proper divisors (543887).

1631649 is an equidigital number, since it uses as much as digits as its factorization.

1631649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 543886.

The product of its digits is 3888, while the sum is 30.

The square root of 1631649 is about 1277.3601684725. The cubic root of 1631649 is about 117.7268651499.

The spelling of 1631649 in words is "one million, six hundred thirty-one thousand, six hundred forty-nine".