1621610501401 has 16 divisors (see below), whose sum is σ = 1788432167808. Its totient is φ = 1470238659120.

The previous prime is 1621610501389. The next prime is 1621610501429. The reversal of 1621610501401 is 1041050161261.

It is not a de Polignac number, because 1621610501401 - 2³³ = 1613020566809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1621610501401.

It is not an unprimeable number, because it can be changed into a prime (1621610501431) 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, 1136701 + ... + 2129626.

It is an arithmetic number, because the mean of its divisors is an integer number (111777010488).

Almost surely, 2^{1621610501401} is an apocalyptic number.

1621610501401 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1621610501401 is a deficient number, since it is larger than the sum of its proper divisors (166821666407).

1621610501401 is an equidigital number, since it uses as much as digits as its factorization.

1621610501401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3266733 (or 3266711 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 28.

Adding to 1621610501401 its reverse (1041050161261), we get a palindrome (2662660662662).

The spelling of 1621610501401 in words is "one trillion, six hundred twenty-one billion, six hundred ten million, five hundred one thousand, four hundred one".