151821540 has 216 divisors, whose sum is σ = 520785720. Its totient is φ = 36951552.

The previous prime is 151821529. The next prime is 151821541. The reversal of 151821540 is 45128151.

It can be written as a sum of positive squares in 4 ways, for example, as 236196 + 151585344 = 486^2 + 12312^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (151821541) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1705816 + ... + 1705904.

It is an arithmetic number, because the mean of its divisors is an integer number (2411045).

Almost surely, 2^151821540 is an apocalyptic number.

151821540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 151821540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (260392860).

151821540 is an abundant number, since it is smaller than the sum of its proper divisors (368964180).

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

151821540 is an equidigital number, since it uses as much as digits as its factorization.

151821540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 27.

The square root of 151821540 is about 12321.5883716346. The cubic root of 151821540 is about 533.4713870047.

Adding to 151821540 its reverse (45128151), we get a palindrome (196949691).

The spelling of 151821540 in words is "one hundred fifty-one million, eight hundred twenty-one thousand, five hundred forty".