151491978 has 128 divisors (see below), whose sum is σ = 399974400. Its totient is φ = 41990400.

The previous prime is 151491971. The next prime is 151491979. The reversal of 151491978 is 879194151.

It is a happy number.

151491978 is a `hidden beast` number, since 151 + 491 + 9 + 7 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (151491971) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 349650 + ... + 350082.

It is an arithmetic number, because the mean of its divisors is an integer number (3124800).

Almost surely, 2^151491978 is an apocalyptic number.

151491978 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 151491978, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (199987200).

151491978 is an abundant number, since it is smaller than the sum of its proper divisors (248482422).

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

151491978 is a wasteful number, since it uses less digits than its factorization.

151491978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 505 (or 499 counting only the distinct ones).

The product of its digits is 90720, while the sum is 45.

The square root of 151491978 is about 12308.2077493029. The cubic root of 151491978 is about 533.0851017568.

The spelling of 151491978 in words is "one hundred fifty-one million, four hundred ninety-one thousand, nine hundred seventy-eight".