20312101551 has 64 divisors (see below), whose sum is σ = 33789450240. Its totient is φ = 10588631040.

The previous prime is 20312101501. The next prime is 20312101567. The reversal of 20312101551 is 15510121302.

It is not a de Polignac number, because 20312101551 - 2⁷ = 20312101423 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20312101501) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2293590 + ... + 2302428.

It is an arithmetic number, because the mean of its divisors is an integer number (527960160).

Almost surely, 2^20312101551 is an apocalyptic number.

20312101551 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

20312101551 is a deficient number, since it is larger than the sum of its proper divisors (13477348689).

20312101551 is a wasteful number, since it uses less digits than its factorization.

20312101551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9064.

The product of its (nonzero) digits is 300, while the sum is 21.

Adding to 20312101551 its reverse (15510121302), we get a palindrome (35822222853).

The spelling of 20312101551 in words is "twenty billion, three hundred twelve million, one hundred one thousand, five hundred fifty-one".