406680906001561 has 9 divisors (see below), whose sum is σ = 425131942371871. Its totient is φ = 388998683820472.

The previous prime is 406680906001549. The next prime is 406680906001583. The reversal of 406680906001561 is 165100609086604.

The square root of 406680906001561 is 20166331.

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., 371624512329225 + 35056393672336 = 19277565^2 + 5920844^2 .

It is not a de Polignac number, because 406680906001561 - 2⁴¹ = 404481882746009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 406680906001499 and 406680906001508.

It is not an unprimeable number, because it can be changed into a prime (406680906002561) 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, 463387215 + ... + 464264011.

Almost surely, 2^{406680906001561} is an apocalyptic number.

406680906001561 is the 20166331-st square number.

406680906001561 is the 10083166-th centered octagonal number.

It is an amenable number.

406680906001561 is a deficient number, since it is larger than the sum of its proper divisors (18451036370310).

406680906001561 is an frugal number, since it uses more digits than its factorization.

406680906001561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1753640 (or 876820 counting only the distinct ones).

The product of its (nonzero) digits is 1866240, while the sum is 52.

The spelling of 406680906001561 in words is "four hundred six trillion, six hundred eighty billion, nine hundred six million, one thousand, five hundred sixty-one".