155558640 has 80 divisors (see below), whose sum is σ = 485031456. Its totient is φ = 41241600.

The previous prime is 155558629. The next prime is 155558671. The reversal of 155558640 is 46855551.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 41650 + ... + 45230.

Almost surely, 2^155558640 is an apocalyptic number.

155558640 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 155558640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (242515728).

155558640 is an abundant number, since it is smaller than the sum of its proper divisors (329472816).

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

155558640 is a wasteful number, since it uses less digits than its factorization.

155558640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3778 (or 3772 counting only the distinct ones).

The product of its (nonzero) digits is 120000, while the sum is 39.

The square root of 155558640 is about 12472.3149415014. The cubic root of 155558640 is about 537.8131033164.

The spelling of 155558640 in words is "one hundred fifty-five million, five hundred fifty-eight thousand, six hundred forty".