1621199445 has 16 divisors (see below), whose sum is σ = 2630454912. Its totient is φ = 852461120.

The previous prime is 1621199429. The next prime is 1621199473. The reversal of 1621199445 is 5449911261.

It is a happy number.

It is not a de Polignac number, because 1621199445 - 2⁴ = 1621199429 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1621199397 and 1621199406.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 760062 + ... + 762191.

It is an arithmetic number, because the mean of its divisors is an integer number (164403432).

Almost surely, 2^1621199445 is an apocalyptic number.

1621199445 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1621199445 is a deficient number, since it is larger than the sum of its proper divisors (1009255467).

1621199445 is a wasteful number, since it uses less digits than its factorization.

1621199445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1522332.

The product of its digits is 77760, while the sum is 42.

The square root of 1621199445 is about 40264.1210632990. The cubic root of 1621199445 is about 1174.7500769189.

The spelling of 1621199445 in words is "one billion, six hundred twenty-one million, one hundred ninety-nine thousand, four hundred forty-five".