1663606451 has 16 divisors (see below), whose sum is σ = 1915770528. Its totient is φ = 1430976000.

The previous prime is 1663606397. The next prime is 1663606463. The reversal of 1663606451 is 1546063661.

It is a cyclic number.

It is not a de Polignac number, because 1663606451 - 2⁶ = 1663606387 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1663606471) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14945 + ... + 59586.

It is an arithmetic number, because the mean of its divisors is an integer number (119735658).

Almost surely, 2^1663606451 is an apocalyptic number.

1663606451 is a deficient number, since it is larger than the sum of its proper divisors (252164077).

1663606451 is a wasteful number, since it uses less digits than its factorization.

1663606451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74662.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 1663606451 is about 40787.3319916858. The cubic root of 1663606451 is about 1184.9049995351.

The spelling of 1663606451 in words is "one billion, six hundred sixty-three million, six hundred six thousand, four hundred fifty-one".