1662212981 has 16 divisors (see below), whose sum is σ = 2020152960. Its totient is φ = 1346761920.

The previous prime is 1662212953. The next prime is 1662212989. The reversal of 1662212981 is 1892122661.

It is a cyclic number.

It is not a de Polignac number, because 1662212981 - 2¹⁸ = 1661950837 is a prime.

It is a super-2 number, since 2×1662212981² = 5525903988409812722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1662212989) 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, 196265 + ... + 204558.

It is an arithmetic number, because the mean of its divisors is an integer number (126259560).

Almost surely, 2^1662212981 is an apocalyptic number.

1662212981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1662212981 is a deficient number, since it is larger than the sum of its proper divisors (357939979).

1662212981 is a wasteful number, since it uses less digits than its factorization.

1662212981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400876.

The product of its digits is 20736, while the sum is 38.

The square root of 1662212981 is about 40770.2462710247. The cubic root of 1662212981 is about 1184.5740737544.

The spelling of 1662212981 in words is "one billion, six hundred sixty-two million, two hundred twelve thousand, nine hundred eighty-one".