1651661671 has 16 divisors (see below), whose sum is σ = 1926021888. Its totient is φ = 1401188800.

The previous prime is 1651661653. The next prime is 1651661677. The reversal of 1651661671 is 1761661561.

It is not a de Polignac number, because 1651661671 - 2²⁷ = 1517443943 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 (1651661677) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69241 + ... + 89986.

It is an arithmetic number, because the mean of its divisors is an integer number (120376368).

Almost surely, 2^1651661671 is an apocalyptic number.

1651661671 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1651661671 is a deficient number, since it is larger than the sum of its proper divisors (274360217).

1651661671 is a wasteful number, since it uses less digits than its factorization.

1651661671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159302.

The product of its digits is 45360, while the sum is 40.

The square root of 1651661671 is about 40640.6406322538. The cubic root of 1651661671 is about 1182.0622920705.

It can be divided in two parts, 16516 and 61671, that added together give a palindrome (78187).

The spelling of 1651661671 in words is "one billion, six hundred fifty-one million, six hundred sixty-one thousand, six hundred seventy-one".