1672137981 has 6 divisors (see below), whose sum is σ = 2415310430. Its totient is φ = 1114758648.

The previous prime is 1672137979. The next prime is 1672137991. The reversal of 1672137981 is 1897312761.

It can be written as a sum of positive squares in only one way, i.e., 918635481 + 753502500 = 30309^2 + 27450^2 .

It is not a de Polignac number, because 1672137981 - 2¹ = 1672137979 is a prime.

It is a super-2 number, since 2×1672137981² = 5592090855005512722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1672137991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 92896546 + ... + 92896563.

Almost surely, 2^1672137981 is an apocalyptic number.

It is an amenable number.

1672137981 is a deficient number, since it is larger than the sum of its proper divisors (743172449).

1672137981 is a wasteful number, since it uses less digits than its factorization.

1672137981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185793115 (or 185793112 counting only the distinct ones).

The product of its digits is 127008, while the sum is 45.

The square root of 1672137981 is about 40891.7837835426. The cubic root of 1672137981 is about 1186.9270764802.

The spelling of 1672137981 in words is "one billion, six hundred seventy-two million, one hundred thirty-seven thousand, nine hundred eighty-one".