1631071994 has 4 divisors (see below), whose sum is σ = 2446607994. Its totient is φ = 815535996.

The previous prime is 1631071993. The next prime is 1631072011. The reversal of 1631071994 is 4991701361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 4991701361 = 5717 ⋅873133.

It can be written as a sum of positive squares in only one way, i.e., 1339926025 + 291145969 = 36605^2 + 17063^2 .

It is a super-2 number, since 2×1631071994² = 5320791699222272072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1631071993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 407767997 + ... + 407768000.

Almost surely, 2^1631071994 is an apocalyptic number.

1631071994 is a deficient number, since it is larger than the sum of its proper divisors (815536000).

1631071994 is an equidigital number, since it uses as much as digits as its factorization.

1631071994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815535999.

The product of its (nonzero) digits is 40824, while the sum is 41.

The square root of 1631071994 is about 40386.5323344305. The cubic root of 1631071994 is about 1177.1298611981.

The spelling of 1631071994 in words is "one billion, six hundred thirty-one million, seventy-one thousand, nine hundred ninety-four".