155640408 has 64 divisors (see below), whose sum is σ = 485118720. Its totient is φ = 40425600.

The previous prime is 155640391. The next prime is 155640409. The reversal of 155640408 is 804046551.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155640409) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40263 + ... + 43958.

It is an arithmetic number, because the mean of its divisors is an integer number (7579980).

Almost surely, 2^155640408 is an apocalyptic number.

It is an amenable number.

155640408 is an abundant number, since it is smaller than the sum of its proper divisors (329478312).

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

155640408 is a wasteful number, since it uses less digits than its factorization.

155640408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84248 (or 84244 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 33.

The square root of 155640408 is about 12475.5924909401. The cubic root of 155640408 is about 537.9073190173.

Adding to 155640408 its reverse (804046551), we get a palindrome (959686959).

The spelling of 155640408 in words is "one hundred fifty-five million, six hundred forty thousand, four hundred eight".