154778442 has 64 divisors (see below), whose sum is σ = 386770944. Its totient is φ = 40201920.

The previous prime is 154778413. The next prime is 154778447. The reversal of 154778442 is 244877451.

It is a super-2 number, since 2×154778442² = 47912732215894728, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 154778394 and 154778403.

It is not an unprimeable number, because it can be changed into a prime (154778447) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34467 + ... + 38697.

It is an arithmetic number, because the mean of its divisors is an integer number (6043296).

Almost surely, 2^154778442 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 154778442, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (193385472).

154778442 is an abundant number, since it is smaller than the sum of its proper divisors (231992502).

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

154778442 is a wasteful number, since it uses less digits than its factorization.

154778442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4323.

The product of its digits is 250880, while the sum is 42.

The square root of 154778442 is about 12440.9984326018. The cubic root of 154778442 is about 536.9124693914.

Subtracting 154778442 from its reverse (244877451), we obtain a palindrome (90099009).

The spelling of 154778442 in words is "one hundred fifty-four million, seven hundred seventy-eight thousand, four hundred forty-two".