787814232921 has 15 divisors (see below), whose sum is σ = 1176870231823. Its totient is φ = 525204163080.

The previous prime is 787814232901. The next prime is 787814232949. The reversal of 787814232921 is 129232418787.

The square root of 787814232921 is 887589.

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

It can be written as a sum of positive squares in only one way, i.e., 787015605321 + 798627600 = 887139^2 + 28260^2 .

It is not a de Polignac number, because 787814232921 - 2¹¹ = 787814230873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (787814232901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 7938991 + ... + 8037611.

Almost surely, 2^787814232921 is an apocalyptic number.

787814232921 is the 887589-th square number.

787814232921 is the 443795-th centered octagonal number.

It is an amenable number.

787814232921 is a deficient number, since it is larger than the sum of its proper divisors (389055998902).

787814232921 is an frugal number, since it uses more digits than its factorization.

787814232921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197254 (or 98624 counting only the distinct ones).

The product of its digits is 2709504, while the sum is 54.

The spelling of 787814232921 in words is "seven hundred eighty-seven billion, eight hundred fourteen million, two hundred thirty-two thousand, nine hundred twenty-one".