207987997960521 has 45 divisors (see below), whose sum is σ = 321050158469469. Its totient is φ = 134183209213800.

The previous prime is 207987997960487. The next prime is 207987997960543. The reversal of 207987997960521 is 125069799789702.

The square root of 207987997960521 is 14421789.

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

207987997960521 is a `hidden beast` number, since 2 + 0 + 7 + 9 + 87 + 9 + 9 + 7 + 9 + 6 + 0 + 521 = 666.

It is not a de Polignac number, because 207987997960521 - 2¹¹ = 207987997958473 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is not an unprimeable number, because it can be changed into a prime (207987947960521) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 4023653286 + ... + 4023704976.

Almost surely, 2^{207987997960521} is an apocalyptic number.

207987997960521 is the 14421789-th square number.

207987997960521 is the 7210895-th centered octagonal number.

It is an amenable number.

207987997960521 is a deficient number, since it is larger than the sum of its proper divisors (113062160508948).

207987997960521 is an frugal number, since it uses more digits than its factorization.

207987997960521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103456 (or 51725 counting only the distinct ones).

The product of its (nonzero) digits is 2160406080, while the sum is 81.

207987997960521 divided by its sum of digits (81) gives a square (2567753061241 = 1602421²).

The spelling of 207987997960521 in words is "two hundred seven trillion, nine hundred eighty-seven billion, nine hundred ninety-seven million, nine hundred sixty thousand, five hundred twenty-one".