151997778 has 24 divisors (see below), whose sum is σ = 329694300. Its totient is φ = 50609664.

The previous prime is 151997773. The next prime is 151997789. The reversal of 151997778 is 877799151.

It can be written as a sum of positive squares in 2 ways, for example, as 151954929 + 42849 = 12327^2 + 207^2 .

It is not an unprimeable number, because it can be changed into a prime (151997771) 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 11 ways as a sum of consecutive naturals, for example, 13978 + ... + 22346.

Almost surely, 2^151997778 is an apocalyptic number.

151997778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

151997778 is an abundant number, since it is smaller than the sum of its proper divisors (177696522).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

151997778 is a wasteful number, since it uses less digits than its factorization.

151997778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9386 (or 9383 counting only the distinct ones).

The product of its digits is 1111320, while the sum is 54.

The square root of 151997778 is about 12328.7378916092. The cubic root of 151997778 is about 533.6777292105.

The spelling of 151997778 in words is "one hundred fifty-one million, nine hundred ninety-seven thousand, seven hundred seventy-eight".