1661312467 has 2 divisors, whose sum is σ = 1661312468. Its totient is φ = 1661312466.

The previous prime is 1661312459. The next prime is 1661312483. The reversal of 1661312467 is 7642131661.

It is a weak prime.

It is an emirp because it is prime and its reverse (7642131661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1661312467 - 2³ = 1661312459 is a prime.

It is a super-2 number, since 2×1661312467² = 5519918226019252178, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1661312407) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830656233 + 830656234.

It is an arithmetic number, because the mean of its divisors is an integer number (830656234).

Almost surely, 2^1661312467 is an apocalyptic number.

1661312467 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661312467 is an equidigital number, since it uses as much as digits as its factorization.

1661312467 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36288, while the sum is 37.

The square root of 1661312467 is about 40759.2010103240. The cubic root of 1661312467 is about 1184.3601183743.

The spelling of 1661312467 in words is "one billion, six hundred sixty-one million, three hundred twelve thousand, four hundred sixty-seven".