1234678767921 has 9 divisors (see below), whose sum is σ = 1783429702041. Its totient is φ = 823116956292.

The previous prime is 1234678767919. The next prime is 1234678767929. The reversal of 1234678767921 is 1297678764321.

The square root of 1234678767921 is 1111161.

It is a perfect power (a square), and thus also a powerful number.

1234678767921 is a `hidden beast` number, since 1 + 2 + 3 + 467 + 87 + 6 + 7 + 92 + 1 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 1234678767921 - 2¹ = 1234678767919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1234678767929) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 3148290 + ... + 3518676.

Almost surely, 2^{1234678767921} is an apocalyptic number.

1234678767921 is the 1111161-st square number.

1234678767921 is the 555581-st centered octagonal number.

It is an amenable number.

1234678767921 is a deficient number, since it is larger than the sum of its proper divisors (548750934120).

1234678767921 is an frugal number, since it uses more digits than its factorization.

1234678767921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 740780 (or 370390 counting only the distinct ones).

The product of its digits is 42674688, while the sum is 63.

The spelling of 1234678767921 in words is "one trillion, two hundred thirty-four billion, six hundred seventy-eight million, seven hundred sixty-seven thousand, nine hundred twenty-one".