1960651981 has 4 divisors (see below), whose sum is σ = 2028260700. Its totient is φ = 1893043264.

The previous prime is 1960651969. The next prime is 1960651999. The reversal of 1960651981 is 1891560691.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1891560691 = 1213 ⋅1559407.

It can be written as a sum of positive squares in 2 ways, for example, as 795522025 + 1165129956 = 28205^2 + 34134^2 .

It is a cyclic number.

It is not a de Polignac number, because 1960651981 - 2⁷ = 1960651853 is a prime.

It is a super-2 number, since 2×1960651981² = 7688312381198448722, 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 (1960651921) 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, 33804316 + ... + 33804373.

It is an arithmetic number, because the mean of its divisors is an integer number (507065175).

Almost surely, 2^1960651981 is an apocalyptic number.

It is an amenable number.

1960651981 is a deficient number, since it is larger than the sum of its proper divisors (67608719).

1960651981 is an equidigital number, since it uses as much as digits as its factorization.

1960651981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67608718.

The product of its (nonzero) digits is 116640, while the sum is 46.

The square root of 1960651981 is about 44279.2500049402. The cubic root of 1960651981 is about 1251.6036975900.

The spelling of 1960651981 in words is "one billion, nine hundred sixty million, six hundred fifty-one thousand, nine hundred eighty-one".