155715840 has 216 divisors, whose sum is σ = 616045248. Its totient is φ = 35573760.

The previous prime is 155715817. The next prime is 155715863. The reversal of 155715840 is 48517551.

155715840 is a `hidden beast` number, since 1 + 5 + 5 + 71 + 584 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (155715817) and next prime (155715863).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a zygodrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 155715795 and 155715804.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 79675 + ... + 81605.

Almost surely, 2^155715840 is an apocalyptic number.

155715840 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 155715840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (308022624).

155715840 is an abundant number, since it is smaller than the sum of its proper divisors (460329408).

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

155715840 is a wasteful number, since it uses less digits than its factorization.

155715840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1965 (or 1948 counting only the distinct ones).

The product of its (nonzero) digits is 28000, while the sum is 36.

The square root of 155715840 is about 12478.6153077976. The cubic root of 155715840 is about 537.9942049191.

The spelling of 155715840 in words is "one hundred fifty-five million, seven hundred fifteen thousand, eight hundred forty".