201621440 has 28 divisors (see below), whose sum is σ = 480111816. Its totient is φ = 80648448.

The previous prime is 201621437. The next prime is 201621451. The reversal of 201621440 is 44126102.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 314714 + ... + 315353.

Almost surely, 2^201621440 is an apocalyptic number.

201621440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

201621440 is an abundant number, since it is smaller than the sum of its proper divisors (278490376).

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

201621440 is an equidigital number, since it uses as much as digits as its factorization.

201621440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 630084 (or 630074 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 20.

The square root of 201621440 is about 14199.3464638342. The cubic root of 201621440 is about 586.3796690818.

Adding to 201621440 its reverse (44126102), we get a palindrome (245747542).

The spelling of 201621440 in words is "two hundred one million, six hundred twenty-one thousand, four hundred forty".