981392094721 has 4 divisors (see below), whose sum is σ = 981543714372. Its totient is φ = 981240475072.

The previous prime is 981392094701. The next prime is 981392094737. The reversal of 981392094721 is 127490293189.

It is a happy number.

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 196369514496 + 785022580225 = 443136^2 + 886015^2 .

It is a cyclic number.

It is not a de Polignac number, because 981392094721 - 2¹⁹ = 981391570433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981392094701) 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, 75800116 + ... + 75813061.

It is an arithmetic number, because the mean of its divisors is an integer number (245385928593).

Almost surely, 2^981392094721 is an apocalyptic number.

It is an amenable number.

981392094721 is a deficient number, since it is larger than the sum of its proper divisors (151619651).

981392094721 is a wasteful number, since it uses less digits than its factorization.

981392094721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151619650.

The product of its (nonzero) digits is 1959552, while the sum is 55.

The spelling of 981392094721 in words is "nine hundred eighty-one billion, three hundred ninety-two million, ninety-four thousand, seven hundred twenty-one".