155897220 has 96 divisors (see below), whose sum is σ = 458825472. Its totient is φ = 39474688.

The previous prime is 155897219. The next prime is 155897239. The reversal of 155897220 is 22798551.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 238414 + ... + 239066.

It is an arithmetic number, because the mean of its divisors is an integer number (4779432).

Almost surely, 2^155897220 is an apocalyptic number.

155897220 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 155897220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (229412736).

155897220 is an abundant number, since it is smaller than the sum of its proper divisors (302928252).

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

155897220 is a wasteful number, since it uses less digits than its factorization.

155897220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 861 (or 859 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 39.

The square root of 155897220 is about 12485.8808259570. The cubic root of 155897220 is about 538.2030116047.

The spelling of 155897220 in words is "one hundred fifty-five million, eight hundred ninety-seven thousand, two hundred twenty".