121781456782 has 16 divisors (see below), whose sum is σ = 185211104832. Its totient is φ = 60044751360.

The previous prime is 121781456777. The next prime is 121781456789. The reversal of 121781456782 is 287654187121.

It is a super-2 number, since 2×121781456782² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121781456789) 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, 683998 + ... + 843454.

It is an arithmetic number, because the mean of its divisors is an integer number (11575694052).

Almost surely, 2^121781456782 is an apocalyptic number.

121781456782 is a deficient number, since it is larger than the sum of its proper divisors (63429648050).

121781456782 is a wasteful number, since it uses less digits than its factorization.

121781456782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 164763.

The product of its digits is 1505280, while the sum is 52.

The spelling of 121781456782 in words is "one hundred twenty-one billion, seven hundred eighty-one million, four hundred fifty-six thousand, seven hundred eighty-two".