1661984481 has 8 divisors (see below), whose sum is σ = 2346331104. Its totient is φ = 1042813760.

The previous prime is 1661984479. The next prime is 1661984483. The reversal of 1661984481 is 1844891661.

It is an interprime number because it is at equal distance from previous prime (1661984479) and next prime (1661984483).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1661984481 - 2¹ = 1661984479 is a prime.

It is a super-2 number, since 2×1661984481² = 5524384830169678722, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1661984481.

It is not an unprimeable number, because it can be changed into a prime (1661984483) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16293915 + ... + 16294016.

It is an arithmetic number, because the mean of its divisors is an integer number (293291388).

Almost surely, 2^1661984481 is an apocalyptic number.

It is an amenable number.

1661984481 is a deficient number, since it is larger than the sum of its proper divisors (684346623).

1661984481 is a wasteful number, since it uses less digits than its factorization.

1661984481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32587951.

The product of its digits is 331776, while the sum is 48.

The square root of 1661984481 is about 40767.4438860226. The cubic root of 1661984481 is about 1184.5197911840.

The spelling of 1661984481 in words is "one billion, six hundred sixty-one million, nine hundred eighty-four thousand, four hundred eighty-one".