1621366560 has 144 divisors (see below), whose sum is σ = 6035964480. Its totient is φ = 393054720.

The previous prime is 1621366547. The next prime is 1621366561. The reversal of 1621366560 is 656631261.

1621366560 is a `hidden beast` number, since 1 + 62 + 1 + 36 + 6 + 560 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1621366561) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 35340 + ... + 67019.

It is an arithmetic number, because the mean of its divisors is an integer number (41916420).

Almost surely, 2^1621366560 is an apocalyptic number.

1621366560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1621366560 is an abundant number, since it is smaller than the sum of its proper divisors (4414597920).

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

1621366560 is a wasteful number, since it uses less digits than its factorization.

1621366560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102391 (or 102380 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 36.

The square root of 1621366560 is about 40266.1962444927. The cubic root of 1621366560 is about 1174.7904403701.

The spelling of 1621366560 in words is "one billion, six hundred twenty-one million, three hundred sixty-six thousand, five hundred sixty".