981257997726 has 12 divisors (see below), whose sum is σ = 2126058995112. Its totient is φ = 327085999236.

The previous prime is 981257997721. The next prime is 981257997743. The reversal of 981257997726 is 627799752189.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (981257997721) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 27257166586 + ... + 27257166621.

It is an arithmetic number, because the mean of its divisors is an integer number (177171582926).

Almost surely, 2^981257997726 is an apocalyptic number.

981257997726 is an abundant number, since it is smaller than the sum of its proper divisors (1144800997386).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

981257997726 is a wasteful number, since it uses less digits than its factorization.

981257997726 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54514333215 (or 54514333212 counting only the distinct ones).

The product of its digits is 240045120, while the sum is 72.

The spelling of 981257997726 in words is "nine hundred eighty-one billion, two hundred fifty-seven million, nine hundred ninety-seven thousand, seven hundred twenty-six".