1621157665050 has 1152 divisors, whose sum is σ = 5888400261120. Its totient is φ = 309899520000.

The previous prime is 1621157665037. The next prime is 1621157665093. The reversal of 1621157665050 is 505667511261.

It is a happy number.

1621157665050 is a `hidden beast` number, since 1 + 6 + 2 + 11 + 576 + 65 + 0 + 5 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 1621157664987 and 1621157665005.

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 2211674484 + ... + 2211675216.

It is an arithmetic number, because the mean of its divisors is an integer number (5111458560).

Almost surely, 2^{1621157665050} is an apocalyptic number.

1621157665050 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1621157665050, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2944200130560).

1621157665050 is an abundant number, since it is smaller than the sum of its proper divisors (4267242596070).

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

1621157665050 is a wasteful number, since it uses less digits than its factorization.

1621157665050 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 900 (or 892 counting only the distinct ones).

The product of its (nonzero) digits is 378000, while the sum is 45.

The spelling of 1621157665050 in words is "one trillion, six hundred twenty-one billion, one hundred fifty-seven million, six hundred sixty-five thousand, fifty".