145421904 has 20 divisors (see below), whose sum is σ = 375673376. Its totient is φ = 48473952.

The previous prime is 145421891. The next prime is 145421923. The reversal of 145421904 is 409124541.

It is a super-2 number, since 2×145421904² = 42295060325970432, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1514764 + ... + 1514859.

Almost surely, 2^145421904 is an apocalyptic number.

It is an amenable number.

145421904 is an abundant number, since it is smaller than the sum of its proper divisors (230251472).

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

145421904 is a wasteful number, since it uses less digits than its factorization.

145421904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3029634 (or 3029628 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 30.

The square root of 145421904 is about 12059.1004639650. The cubic root of 145421904 is about 525.8678363128.

The spelling of 145421904 in words is "one hundred forty-five million, four hundred twenty-one thousand, nine hundred four".