1620908694890 has 8 divisors (see below), whose sum is σ = 2917635650820. Its totient is φ = 648363477952.

The previous prime is 1620908694883. The next prime is 1620908694931. The reversal of 1620908694890 is 984968090261.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1573737633169 + 47171061721 = 1254487^2 + 217189^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×1620908694890² (a number of 25 digits) contains 22 as substring.

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, 81045434735 + ... + 81045434754.

Almost surely, 2^{1620908694890} is an apocalyptic number.

1620908694890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1620908694890 is a deficient number, since it is larger than the sum of its proper divisors (1296726955930).

1620908694890 is a wasteful number, since it uses less digits than its factorization.

1620908694890 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162090869496.

The product of its (nonzero) digits is 13436928, while the sum is 62.

The spelling of 1620908694890 in words is "one trillion, six hundred twenty billion, nine hundred eight million, six hundred ninety-four thousand, eight hundred ninety".