1671997541 has 2 divisors, whose sum is σ = 1671997542. Its totient is φ = 1671997540.

The previous prime is 1671997513. The next prime is 1671997571. The reversal of 1671997541 is 1457991761.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1277776516 + 394221025 = 35746^2 + 19855^2 .

It is a cyclic number.

It is not a de Polignac number, because 1671997541 - 2¹⁰ = 1671996517 is a prime.

It is a super-2 number, since 2×1671997541² = 5591151554220093362, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1671997541.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1671997571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 835998770 + 835998771.

It is an arithmetic number, because the mean of its divisors is an integer number (835998771).

Almost surely, 2^1671997541 is an apocalyptic number.

It is an amenable number.

1671997541 is a deficient number, since it is larger than the sum of its proper divisors (1).

1671997541 is an equidigital number, since it uses as much as digits as its factorization.

1671997541 is an evil number, because the sum of its binary digits is even.

The product of its digits is 476280, while the sum is 50.

The square root of 1671997541 is about 40890.0665321053. The cubic root of 1671997541 is about 1186.8938462270.

The spelling of 1671997541 in words is "one billion, six hundred seventy-one million, nine hundred ninety-seven thousand, five hundred forty-one".