3400172721 has 135 divisors (see below), whose sum is σ = 6088512969. Its totient is φ = 1889276400.

The previous prime is 3400172693. The next prime is 3400172729. The reversal of 3400172721 is 1272710043.

3400172721 = 1³ + 2³ + ... + 341³.

It is a happy number.

The square root of 3400172721 is 58311.

It is a perfect power (a square), and thus also a powerful number.

It is not a de Polignac number, because 3400172721 - 2⁵ = 3400172689 is a prime.

It is a super-2 number, since 2×3400172721² = 23122349065265087682, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (3400172729) by changing a digit.

It is a polite number, since it can be written in 134 ways as a sum of consecutive naturals, for example, 109682976 + ... + 109683006.

Almost surely, 2^3400172721 is an apocalyptic number.

3400172721 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

3400172721 is the 58311-st square number.

3400172721 is the 29156-th centered octagonal number.

It is an amenable number.

3400172721 is a deficient number, since it is larger than the sum of its proper divisors (2688340248).

3400172721 is a wasteful number, since it uses less digits than its factorization.

3400172721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 64 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 27.

The cubic root of 3400172721 is about 1503.7200584831.

Adding to 3400172721 its reverse (1272710043), we get a palindrome (4672882764).

It can be divided in two parts, 3400 and 172721, that added together give a triangular number (176121 = T₅₉₃).

The spelling of 3400172721 in words is "three billion, four hundred million, one hundred seventy-two thousand, seven hundred twenty-one".