1237996981 has 4 divisors (see below), whose sum is σ = 1333227532. Its totient is φ = 1142766432.

The previous prime is 1237996973. The next prime is 1237996987. The reversal of 1237996981 is 1896997321.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 337456900 + 900540081 = 18370^2 + 30009^2 .

It is a cyclic number.

It is not a de Polignac number, because 1237996981 - 2³ = 1237996973 is a prime.

It is a super-2 number, since 2×1237996981² = 3065273049930228722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1237996987) 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, 47615256 + ... + 47615281.

It is an arithmetic number, because the mean of its divisors is an integer number (333306883).

Almost surely, 2^1237996981 is an apocalyptic number.

It is an amenable number.

1237996981 is a deficient number, since it is larger than the sum of its proper divisors (95230551).

1237996981 is an equidigital number, since it uses as much as digits as its factorization.

1237996981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95230550.

The product of its digits is 1469664, while the sum is 55.

The square root of 1237996981 is about 35185.1812699608. The cubic root of 1237996981 is about 1073.7582867691.

The spelling of 1237996981 in words is "one billion, two hundred thirty-seven million, nine hundred ninety-six thousand, nine hundred eighty-one".