1618556450625 has 45 divisors (see below), whose sum is σ = 2921630660949. Its totient is φ = 863179218000.

The previous prime is 1618556450611. The next prime is 1618556450633. The reversal of 1618556450625 is 5260546558161.

The square root of 1618556450625 is 1272225.

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

1618556450625 is a `hidden beast` number, since 1 + 6 + 1 + 8 + 5 + 5 + 6 + 4 + 5 + 0 + 625 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 126894825729 + 1491661624896 = 356223^2 + 1221336^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 1618556450625 - 2²⁹ = 1618019579713 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 95408394 + ... + 95425356.

Almost surely, 2^{1618556450625} is an apocalyptic number.

1618556450625 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1618556450625 is the 1272225-th square number.

1618556450625 is the 636113-rd centered octagonal number.

It is an amenable number.

1618556450625 is a deficient number, since it is larger than the sum of its proper divisors (1303074210324).

1618556450625 is an frugal number, since it uses more digits than its factorization.

1618556450625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33952 (or 16971 counting only the distinct ones).

The product of its (nonzero) digits is 8640000, while the sum is 54.

The spelling of 1618556450625 in words is "one trillion, six hundred eighteen billion, five hundred fifty-six million, four hundred fifty thousand, six hundred twenty-five".