1453991978 has 8 divisors (see below), whose sum is σ = 2181186468. Its totient is φ = 726929824.

The previous prime is 1453991971. The next prime is 1453992079. The reversal of 1453991978 is 8791993541.

It can be written as a sum of positive squares in 2 ways, for example, as 1453363129 + 628849 = 38123^2 + 793^2 .

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

It is a super-2 number, since 2×1453991978² = 4228185344176704968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1453991971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1700 + ... + 53952.

Almost surely, 2^1453991978 is an apocalyptic number.

1453991978 is a deficient number, since it is larger than the sum of its proper divisors (727194490).

1453991978 is a wasteful number, since it uses less digits than its factorization.

1453991978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66168.

The product of its digits is 2449440, while the sum is 56.

The square root of 1453991978 is about 38131.2467406981. The cubic root of 1453991978 is about 1132.8889396307. Note that the first 3 decimals are identical.

The spelling of 1453991978 in words is "one billion, four hundred fifty-three million, nine hundred ninety-one thousand, nine hundred seventy-eight".