1661322481 has 16 divisors (see below), whose sum is σ = 2060327808. Its totient is φ = 1304409600.

The previous prime is 1661322479. The next prime is 1661322493. The reversal of 1661322481 is 1842231661.

It is not a de Polignac number, because 1661322481 - 2¹ = 1661322479 is a prime.

It is a super-2 number, since 2×1661322481² = 5519984771751990722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1661322461) 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, 57760 + ... + 81601.

It is an arithmetic number, because the mean of its divisors is an integer number (128770488).

Almost surely, 2^1661322481 is an apocalyptic number.

It is an amenable number.

1661322481 is a deficient number, since it is larger than the sum of its proper divisors (399005327).

1661322481 is a wasteful number, since it uses less digits than its factorization.

1661322481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 139512.

The product of its digits is 13824, while the sum is 34.

The square root of 1661322481 is about 40759.3238535675. The cubic root of 1661322481 is about 1184.3624980508.

The spelling of 1661322481 in words is "one billion, six hundred sixty-one million, three hundred twenty-two thousand, four hundred eighty-one".