145621553 has 8 divisors (see below), whose sum is σ = 181554240. Its totient is φ = 113471280.

The previous prime is 145621537. The next prime is 145621577. The reversal of 145621553 is 355126541.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 145621553 - 2⁴ = 145621537 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (145623553) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 945518 + ... + 945671.

It is an arithmetic number, because the mean of its divisors is an integer number (22694280).

Almost surely, 2^145621553 is an apocalyptic number.

It is an amenable number.

145621553 is a deficient number, since it is larger than the sum of its proper divisors (35932687).

145621553 is a wasteful number, since it uses less digits than its factorization.

145621553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1891207.

The product of its digits is 18000, while the sum is 32.

The square root of 145621553 is about 12067.3755638913. The cubic root of 145621553 is about 526.1083800344.

The spelling of 145621553 in words is "one hundred forty-five million, six hundred twenty-one thousand, five hundred fifty-three".