1396976981 has 4 divisors (see below), whose sum is σ = 1397193612. Its totient is φ = 1396760352.

The previous prime is 1396976929. The next prime is 1396977007. The reversal of 1396976981 is 1896796931.

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 382554481 + 1014422500 = 19559^2 + 31850^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1396976981 is a prime.

It is a super-2 number, since 2×1396976981² = 3903089370887748722, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1396976981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1396976381) 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, 98336 + ... + 111641.

It is an arithmetic number, because the mean of its divisors is an integer number (349298403).

Almost surely, 2^1396976981 is an apocalyptic number.

It is an amenable number.

1396976981 is a deficient number, since it is larger than the sum of its proper divisors (216631).

1396976981 is an equidigital number, since it uses as much as digits as its factorization.

1396976981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 216630.

The product of its digits is 4408992, while the sum is 59.

The square root of 1396976981 is about 37376.1552463599. The cubic root of 1396976981 is about 1117.8831670885.

The spelling of 1396976981 in words is "one billion, three hundred ninety-six million, nine hundred seventy-six thousand, nine hundred eighty-one".