1667428731 has 12 divisors (see below), whose sum is σ = 2550185352. Its totient is φ = 1046229696.

The previous prime is 1667428709. The next prime is 1667428783. The reversal of 1667428731 is 1378247661.

It is not a de Polignac number, because 1667428731 - 2⁷ = 1667428603 is a prime.

It is a super-2 number, since 2×1667428731² = 5560637145928540722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1667423731) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5448961 + ... + 5449266.

It is an arithmetic number, because the mean of its divisors is an integer number (212515446).

Almost surely, 2^1667428731 is an apocalyptic number.

1667428731 is a deficient number, since it is larger than the sum of its proper divisors (882756621).

1667428731 is a wasteful number, since it uses less digits than its factorization.

1667428731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10898250 (or 10898247 counting only the distinct ones).

The product of its digits is 338688, while the sum is 45.

The square root of 1667428731 is about 40834.1613235781. The cubic root of 1667428731 is about 1185.8117793968.

The spelling of 1667428731 in words is "one billion, six hundred sixty-seven million, four hundred twenty-eight thousand, seven hundred thirty-one".