621540040 has 64 divisors (see below), whose sum is σ = 1591954560. Its totient is φ = 216184320.

The previous prime is 621540037. The next prime is 621540047. The reversal of 621540040 is 40045126.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 621539993 and 621540020.

It is not an unprimeable number, because it can be changed into a prime (621540047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20589 + ... + 40828.

It is an arithmetic number, because the mean of its divisors is an integer number (24874290).

Almost surely, 2^621540040 is an apocalyptic number.

It is an amenable number.

621540040 is an abundant number, since it is smaller than the sum of its proper divisors (970414520).

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

621540040 is a wasteful number, since it uses less digits than its factorization.

621540040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 61462 (or 61458 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 621540040 is about 24930.7047634037. The cubic root of 621540040 is about 853.4073333992.

Adding to 621540040 its reverse (40045126), we get a palindrome (661585166).

The spelling of 621540040 in words is "six hundred twenty-one million, five hundred forty thousand, forty".