1620907801 has 4 divisors (see below), whose sum is σ = 1628048592. Its totient is φ = 1613767012.

The previous prime is 1620907793. The next prime is 1620907811. The reversal of 1620907801 is 1087090261.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1620907801 - 2³ = 1620907793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1620907811) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3570055 + ... + 3570508.

It is an arithmetic number, because the mean of its divisors is an integer number (407012148).

Almost surely, 2^1620907801 is an apocalyptic number.

It is an amenable number.

1620907801 is a deficient number, since it is larger than the sum of its proper divisors (7140791).

1620907801 is an equidigital number, since it uses as much as digits as its factorization.

1620907801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7140790.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 1620907801 is about 40260.4992641671. The cubic root of 1620907801 is about 1174.6796292104.

The spelling of 1620907801 in words is "one billion, six hundred twenty million, nine hundred seven thousand, eight hundred one".