121681478831 has 8 divisors (see below), whose sum is σ = 132752354304. Its totient is φ = 110612090520.

The previous prime is 121681478761. The next prime is 121681478857. The reversal of 121681478831 is 138874186121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121681478831 is a prime.

It is a super-2 number, since 2×121681478831² (a number of 23 digits) 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 121681478831.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121681478231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 197135 + ... + 531248.

It is an arithmetic number, because the mean of its divisors is an integer number (16594044288).

Almost surely, 2^121681478831 is an apocalyptic number.

121681478831 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121681478831 is a deficient number, since it is larger than the sum of its proper divisors (11070875473).

121681478831 is a wasteful number, since it uses less digits than its factorization.

121681478831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 743581.

The product of its digits is 516096, while the sum is 50.

The spelling of 121681478831 in words is "one hundred twenty-one billion, six hundred eighty-one million, four hundred seventy-eight thousand, eight hundred thirty-one".