155653681 has 4 divisors (see below), whose sum is σ = 163846000. Its totient is φ = 147461364.

The previous prime is 155653637. The next prime is 155653699. The reversal of 155653681 is 186356551.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 186356551 = 47 ⋅3965033.

It is a cyclic number.

It is not a de Polignac number, because 155653681 - 2¹¹ = 155651633 is a prime.

It is a super-2 number, since 2×155653681² = 48456136817699522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155653601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4096131 + ... + 4096168.

It is an arithmetic number, because the mean of its divisors is an integer number (40961500).

Almost surely, 2^155653681 is an apocalyptic number.

It is an amenable number.

155653681 is a deficient number, since it is larger than the sum of its proper divisors (8192319).

155653681 is an equidigital number, since it uses as much as digits as its factorization.

155653681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8192318.

The product of its digits is 108000, while the sum is 40.

The square root of 155653681 is about 12476.1244383021. The cubic root of 155653681 is about 537.9226094786.

The spelling of 155653681 in words is "one hundred fifty-five million, six hundred fifty-three thousand, six hundred eighty-one".