155634421 has 4 divisors (see below), whose sum is σ = 155663200. Its totient is φ = 155605644.

The previous prime is 155634383. The next prime is 155634443. The reversal of 155634421 is 124436551.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 155634421 - 2¹⁵ = 155601653 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155634461) 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, 3561 + ... + 17998.

It is an arithmetic number, because the mean of its divisors is an integer number (38915800).

Almost surely, 2^155634421 is an apocalyptic number.

It is an amenable number.

155634421 is a deficient number, since it is larger than the sum of its proper divisors (28779).

155634421 is an equidigital number, since it uses as much as digits as its factorization.

155634421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28778.

The product of its digits is 14400, while the sum is 31.

The square root of 155634421 is about 12475.3525401088. The cubic root of 155634421 is about 537.9004217244.

The spelling of 155634421 in words is "one hundred fifty-five million, six hundred thirty-four thousand, four hundred twenty-one".