145731440 has 40 divisors (see below), whose sum is σ = 344391648. Its totient is φ = 57335040.

The previous prime is 145731431. The next prime is 145731479. The reversal of 145731440 is 44137541.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10052 + ... + 19811.

Almost surely, 2^145731440 is an apocalyptic number.

145731440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

145731440 is an abundant number, since it is smaller than the sum of its proper divisors (198660208).

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

145731440 is a wasteful number, since it uses less digits than its factorization.

145731440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29937 (or 29931 counting only the distinct ones).

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 145731440 is about 12071.9277665168. The cubic root of 145731440 is about 526.2406817314.

Adding to 145731440 its reverse (44137541), we get a palindrome (189868981).

The spelling of 145731440 in words is "one hundred forty-five million, seven hundred thirty-one thousand, four hundred forty".